《c++程序设计》谭浩强课后习题答案

第一章


1.5题
#include
using namespace std;
int main()
{
cout<<"This"<<"is";
cout<<"a"<<"C++";
cout<<"program.";
return 0;

----------------------------
1.6题
#include
using namespace std;
int main()
{
int a,b,c;
a=10;
b=23;
c=a+b;
cout<<"a+b=";
cout<cout<return 0;
}

------------------------------

1.7七题
#include
using namespace std;
int main()
{
int a,b,c;
int f(int x,int y,int z);
cin>>a>>b>>c;
c=f(a,b,c);
cout<return 0;
}
int f(int x,int y,int z)
{
int m;
if (xelse m=y;
if (zreturn(m);
}

--------------------------------------

1.8题
#include
using namespace std;
int main()
{
int a,b,c;
cin>>a>>b;
c=a+b;
cout<<"a+b="<return 0;
}

----------------------------------------


1.9题
#include
using namespace std;
int main()
{
int a,b,c;
int add(int x,int y);
cin>>a>>b;
c=add(a,b);
cout<<"a+b="<return 0;
}

int add(int x,int y)
{int z;
z=x+y;
return(z);
}
============================================================================================
2.3题
#include
using namespace std;
int main()
{char c1='a',c2='b',c3='c',c4='\101',c5='\116';
cout<cout<<"\t\b"<return 0;
}

-----------------------------

2.4题
#include
using namespace std;
int main()
{char c1='C',c2='+',c3='+';
cout<<"I say: \""<cout<<"\t\t"<<"He says: \"C++ is very interesting!\""<< '\n';
return 0;
}

------------------------------------

2.7题
#include
using namespace std;
int main()
{int i,j,m,n;
i=8;
j=10;
m=++i+j++;
n=(++i)+(++j)+m;
cout<return 0;
}
2.8题
#include
using namespace std;
int main()
{char c1='C', c2='h', c3='i', c4='n', c5='a';
c1+=4;
c2+=4;
c3+=4;
c4+=4;
c5+=4;
cout<<"password is:"<return 0;
}
===========================================================================================

3.2题
#include
#include
using namespace std;
int main ( )
{float h,r,l,s,sq,vq,vz;
const float pi=3.1415926;
cout<<"please enter r,h:";
cin>>r>>h;
l=2*pi*r;
s=r*r*pi;
sq=4*pi*r*r;
vq=3.0/4.0*pi*r*r*r;
vz=pi*r*r*h;
cout<<cout<<"l= "<cout<<"s= "<cout<<"sq="<cout<<"vq="<cout<<"vz="<return 0;
}

-----------------------------------------

3.3题
#include
using namespace std;
int main ()
{float c,f;
cout<<"请输入一个华氏温度:";
cin>>f;
c=(5.0/9.0)*(f-32); //注意5和9要用实型表示,否则5/9值为0
cout<<"

摄氏温度为:"<return 0;
};

3.4题
#include
using namespace std;
int main ( )
{char c1,c2;
cout<<"请输入两个字符c1,c2:";
c1=getchar(); //将输入的第一个字符赋给c1
c2=getchar(); //将输入的第二个字符赋给c2
cout<<"用putchar函数输出结果为:";
putchar(c1);
putchar(c2);
cout<cout<<"用cout语句输出结果为:";
cout<return 0;
}

------------------------------------------------------

3.4题另一解
#include
using namespace std;
int main ( )
{char c1,c2;
cout<<"请输入两个字符c1,c2:";
c1=getchar(); //将输入的第一个字符赋给c1
c2=getchar(); //将输入的第二个字符赋给c2
cout<<"用putchar函数输出结果为:";
putchar(c1);
putchar(44);
putchar(c2);
cout<cout<<"用cout语句输出结果为:";
cout<return 0;
}

-----------------------------------------------


3.5题
#include
using namespace std;
int main ( )
{char c1,c2;
int i1,i2; //定义为整型
cout<<"请输入两个整数i1,i2:";
cin>>i1>>i2;
c1=i1;
c2=i2;
cout<<"按字符输出结果为:"<return 0;
}

------------------------------------------

3.8题
#include
using namespace std;
int main ( )
{ int a=3,b=4,c=5,x,y;
cout<<(a+b>c && b==c)<cout<<(a||b+c && b-c)<cout<<(!(a>b) && !c||1)<cout<<(!(x=a) && (y=b) && 0)<cout<<(!(a+b)+c-1 && b+c/2)<return 0;
}

---------------------------------------------------------


3.9题
include
using namespace std;
int main ( )
{int a,b,c;
cout<<"please enter three integer numbers:";
cin>>a>>b>>c;
if(aif(bcout<<"max="<else
cout<<"max="<else if (acout<<"max="<else
cout<<"max="<cout<return 0;
}

-------------------------------------------------


3.9题另一解
#include
using namespace std;
int main ( )
{int a,b,c,temp,max ;
cout<<"please enter three integer numbers:";
cin>>a>>b>>c;
temp=(a>b)?a:b; /* 将a和b中的大者存入temp中 */
max=(temp>c)?temp:c; /* 将a和b中的大者与c比较，最大者存入max
*/
cout<<"max="<return 0;
}

------------------------------------------------


3.10题
#include
using namespace std;
int main ( )
{int x,y;
cout<<"enter x:";
cin>>x;
if (x<1)
{y=x;
cout<<"x="<}
else if (x<10) // 1≤x＜10
{y=2*x-1;
cout<<"x="<}
else // x≥10
{y=3*x-11;
cout<<"x="<}
cout<<

endl;
return 0;
}

------------------------------------------------

3.11题
#include
using namespace std;
int main ()
{float score;
char grade;
cout<<"please enter score of student:";
cin>>score;
while (score>100||score<0)
{cout<<"data error,enter data again.";
cin>>score;
}
switch(int(score/10))
{case 10:
case 9: grade='A';break;
case 8: grade='B';break;
case 7: grade='C';break;
case 6: grade='D';break;
default:grade='E';
}
cout<<"score is "<return 0;
}

----------------------------------------------------------

3.12题
#include
using namespace std;
int main ()
{long int num;
int indiv,ten,hundred,thousand,ten_thousand,place;
/*分别代表个位,十位,百位,千位,万位和位数
*/
cout<<"enter an integer(0~99999):";
cin>>num;
if (num>9999)
place=5;
else if (num>999)
place=4;
else if (num>99)
place=3;
else if (num>9)
place=2;
else place=1;
cout<<"place="<//计算各位数字
ten_thousand=num/10000;
thousand=(int)(num-ten_thousand*10000)/1000;
hundred=(int)(num-ten_thousand*10000-thousand*1000)/100;
ten=(int)(num-ten_thousand*10000-thousand*1000-hundred*100)/10;
indiv=(int)(num-ten_thousand*10000-thousand*1000-hundred*100-ten*10);
cout<<"original order:";
switch(place)
{case
5:cout<dl;
cout<<"reverse order:";
cout<break;
case 4:cout<cout<<"reverse order:";
cout<break;
case 3:cout<cout<<"reverse order:";
cout<break;
case 2:cout<cout<<"reverse order:";
cout<break;
case 1:cout<cout<<"reverse order:";
cout<break;
}
return 0;
}

------------------------------------------------------------------

3.13题
#include
using namespace std;
int main ()
{ long i; //i为利润
float bonus,bon1,bon2,bon4,bon6,bon10;
bon1=100000*0.1; //利润为10万元时的奖金
bon2=bon1+100000*0.075; //利润为20万元时的奖金
bon4=bon2+100000*0.05; //利润为40万元时的奖金
bon6=bon4+100000*0.03; //利润为60万元时的奖金
bon10=bon6+400000*0.015; //利润为100万元时的奖金
cout<<"enter i:";
cin>>i;
if (i<=100000)
bonus=i*0.1; //利润在10万元以内按10%提成奖金
else if (i<=200000)
bonus=bon1+(i-100000)*0.0

75; //利润在10万元至20万时的奖金
else if (i<=400000)
bonus=bon2+(i-200000)*0.05; //利润在20万元至40万时的奖金
else if (i<=600000)
bonus=bon4+(i-400000)*0.03; //利润在40万元至60万时的奖金
else if (i<=1000000)
bonus=bon6+(i-600000)*0.015; //利润在60万元至100万时的奖金
else
bonus=bon10+(i-1000000)*0.01; //利润在100万元以上时的奖金
cout<<"bonus="<return 0;
}

----------------------------------------------------------


3.13题另一解
#include
using namespace std;
int main ()
{long i;
float bonus,bon1,bon2,bon4,bon6,bon10;
int c;
bon1=100000*0.1;
bon2=bon1+100000*0.075;
bon4=bon2+200000*0.05;
bon6=bon4+200000*0.03;
bon10=bon6+400000*0.015;
cout<<"enter i:";
cin>>i;
c=i/100000;
if (c>10) c=10;
switch(c)
{case 0: bonus=i*0.1; break;
case 1: bonus=bon1+(i-100000)*0.075; break;
case 2:
case 3: bonus=bon2+(i-200000)*0.05;break;
case 4:
case 5: bonus=bon4+(i-400000)*0.03;break;
case 6:
case 7:
case 8:
case 9: bonus=bon6+(i-600000)*0.015; break;
case 10: bonus=bon10+(i-1000000)*0.01;
}
cout<<"bonus="<return 0;
}


-------------------------------------------------------------

3.14题
#include
using namespace std;
int main ()
{int t,a,b,c,d;
cout<<"enter four numbers:";
cin>>a>>b>>c>>d;
cout<<"a="<cout<return 0;
}

--------------------------------------------------------------

3.15题
#include
using namespace std;
int main ()
{int p,r,n,m,temp;
cout<<"please enter two positive integer numbers n,m:";
cin>>n>>m;
if (n{temp=n;
n=m;
m=temp; //把大数放在n中, 小数放在m中
}
p=n*m; //先将n和m的乘积保存在p中, 以便求最小公倍数时用
while (m!=0) //求n和m的最大公约数
{r=n%m;
n=m;
m=r;
}
cout<<"HCF="<cout<<"LCD="<

return 0;
}

-----------------------------------------------------------------

3.16题
#include
using namespace std;
int main ()
{char c;
int letters=0,space=0,digit=0,other=0;
cout<<"enter one line::"<while((c=getchar())!='\n')
{if (c>='a' && c<='z'||c>='A' && c<='Z')
letters++; //字母的个数
else if (c==' ')
space++; //空格的个数
else if (c>='0' && c<='9')
digit++; // 数字的个数
else
other++;
}
cout<<"letter:

"<other:"<return 0;
}

-----------------------------------------------------------


3.17题
#include
using namespace std;
int main ()
{int a,n,i=1,sn=0,tn=0;
cout<<"a,n=:";
cin>>a>>n;
while (i<=n)
{tn=tn+a; //赋值后的tn为i个a组成数的值
sn=sn+tn; //赋值后的sn为多项式前i项之和
a=a*10;
++i;
}
cout<<"a+aa+aaa+...="<return 0;
}

-------------------------------------------------------------

3.18题
#include
using namespace std;
int main ()
{float s=0,t=1;
int n;
for (n=1;n<=20;n++)
{
t=t*n; // 求n!
s=s+t; // 将各项累加
}
cout<<"1!+2!+...+20!="<return 0;
}

-----------------------------------------------------

3.19题
#include
using namespace std;
int main ()
{int i,j,k,n;
cout<<"narcissus numbers are:"<for (n=100;n<1000;n++)
{i=n/100;
j=n/10-i*10;
k=n%10;
if (n == i*i*i + j*j*j + k*k*k)
cout<}
cout<return 0;
}

--------------------------------------------------

3.20题
#include
using namespace std;
int main()
{const int m=1000; // 定义寻找范围
int k1,k2,k3,k4,k5,k6,k7,k8,k9,k10;
int i,a,n,s;
for (a=2;a<=m;a++) // a是2~1000之间的整数，检查它是否为完数
{n=0; // n用来累计a的因子的个数
s=a; // s用来存放尚未求出的因子之和，开始时等于a
for (i=1;iif (a%i==0) // 如果i是a的因子
{n++; // n加1，表示新找到一个因子
s=s-i; // s减去已找到的因子，s的新值是尚未求出的因子
之和
switch(n) // 将找到的因子赋给k1,...,k10
{case 1:
k1=i; break; // 找出的笫1个因子赋给k1
case 2:
k2=i; break; // 找出的笫2个因子赋给k2
case 3:
k3=i; break; // 找出的笫3个因子赋给k3
case 4:
k4=i; break; // 找出的笫4个因子赋给k4
case 5:
k5=i; break; // 找出的笫5个因子赋给k5
case 6:
k6=i; break; // 找出的笫6个因子赋给k6
case 7:
k7=i; break; // 找出的笫7个因子赋给k7
case 8:
k8=i; break; // 找出的笫8个因子赋给k8
case 9:
k9=i; break; // 找出的笫9个因子赋给k9
case 10:
k10=i; break; // 找出的笫10个因子赋给k10
}
}
if (s==0) // s=0表示全部因子都已找到了
{cout<cout<<"its factors are:";
if (n>1) cout<1表示a至少有2个因子
if (n>2) cout<<","<2表示至少有3个因子，

故应再输出一个因子
if (n>3) cout<<","<3表示至少有4个因子，故应再输出一个因子
if (n>4) cout<<","<if (n>5) cout<<","<if (n>6) cout<<","<if (n>7) cout<<","<if (n>8) cout<<","<if (n>9) cout<<","<cout<}
}
return 0;
}


---------------------------------------------------------------



3.20题另一解
#include
using namespace std;
int main()
{int m,s,i;
for (m=2;m<1000;m++)
{s=0;
for (i=1;iif ((m%i)==0) s=s+i;
if(s==m)
{cout<cout<<"its factors are:";
for (i=1;iif (m%i==0) cout<cout<}
}
return 0;
}

-------------------------------------------------------------

3.20题另一解
#include
using namespace std;
int main()
{int k[11];
int i,a,n,s;
for (a=2;a<=1000;a++)
{n=0;
s=a;
for (i=1;iif ((a%i)==0)
{n++;
s=s-i;
k[n]=i; // 将找到的因子赋给k[1]┅k[10]
}
if (s==0)
{cout<cout<<"its factors are:";
for (i=1;icout<cout<}
}
return 0;
}

-----------------------------------

3.21题
#include
using namespace std;
int main()
{int i,t,n=20;
double a=2,b=1,s=0;
for (i=1;i<=n;i++)
{s=s+a/b;
t=a;
a=a+b; // 将前一项分子与分母之和作为下一项的分子
b=t; // 将前一项的分子作为下一项的分母
}
cout<<"sum="<return 0;
}

-----------------------------------------------------------

3.22题
#include
using namespace std;
int main()
{int day,x1,x2;
day=9;
x2=1;
while(day>0)
{x1=(x2+1)*2; // 第1天的桃子数是第2天桃子数加1后的2倍
x2=x1;
day--;
}
cout<<"total="<return 0;
}

3.23题
#include
#include
using namespace std;
int main()
{float a,x0,x1;
cout<<"enter a positive number:";
cin>>a; // 输入a的值
x0=a/2;
x1=(x0+a/x0)/2;
do
{x0=x1;
x1=(x0+a/x0)/2;
}
while(fabs(x0-x1)>=1e-5);
cout<<"The square root of "<return 0;
}

3.24题
#include
using namespace std;
int main()
{int i,k;
for (i=0;i<=3;i++) // 输出上面4行*号
{for (k=0;k<=2*i;k++)
cout<<"*"; // 输出*号
cout<}
for (i=0;i<=2;i++) // 输出下面3行*号
{for (k=0;k<=4-2*i;k++)
cout<<"*"; // 输出*号
cou

t<}
return 0;
}

3.25题
#include
using namespace std;
int main()
{char i,j,k; /* i是a的对手;j是b的对手;k是c的对手*/
for (i='X';i<='Z';i++)
for (j='X';j<='Z';j++)
if (i!=j)
for (k='X';k<='Z';k++)
if (i!=k && j!=k)
if (i!='X' && k!='X' && k!='Z')
cout<<"A--"<return 0;
}
==============================================================================================
4.1题
#include
using namespace std;
int main()
{int hcf(int,int);
int lcd(int,int,int);
int u,v,h,l;
cin>>u>>v;
h=hcf(u,v);
cout<<"H.C.F="<l=lcd(u,v,h);
cout<<"L.C.D="<return 0;
}

int hcf(int u,int v)
{int t,r;
if (v>u)
{t=u;u=v;v=t;}
while ((r=u%v)!=0)
{u=v;
v=r;}
return(v);
}

int lcd(int u,int v,int h)
{return(u*v/h);
}


4.2题
#include
#include
using namespace std;
float x1,x2,disc,p,q;
int main()
{void greater_than_zero(float,float);
void equal_to_zero(float,float);
void smaller_than_zero(float,float);
float a,b,c;
cout<<"input a,b,c:";
cin>>a>>b>>c;
disc=b*b-4*a*c;
cout<<"root:"<if (disc>0)
{
greater_than_zero(a,b);
cout<<"x1="<}
else if (disc==0)
{equal_to_zero(a,b);
cout<<"x1="<}
else
{smaller_than_zero(a,b);
cout<<"x1="<cout<<"x2="<}
return 0;
}

void greater_than_zero(float a,float b) /* 定义一个函数，用来求disc>0时方
程的根 */
{x1=(-b+sqrt(disc))/(2*a);
x2=(-b-sqrt(disc))/(2*a);
}

void equal_to_zero(float a,float b) /* 定义一个函数，用来求disc=0时方程
的根 */
{
x1=x2=(-b)/(2*a);
}

void smaller_than_zero(float a,float b) /* 定义一个函数，用来求disc<0时方
程的根 */
{
p=-b/(2*a);
q=sqrt(-disc)/(2*a);
}

4.3题
#include
using namespace std;
int main()
{int prime(int); /* 函数原型声明 */
int n;
cout<<"input an integer:";
cin>>n;
if (prime(n))
cout<else
cout<return 0;
}

int prime(int n)
{int flag=1,i;
for (i=2;iif (n%i==0)
flag=0;
return(flag);
}


4.4题
#include
using namespace std;
int main()
{int fac(int);
int a,b,c,sum=0;
cout<<"enter a,b,c:";
cin>>a>>b>>c;
sum=sum+fac(a)+fac(b)+fac(c);
cout<return 0;
}

int fac(int n)
{int f=1;
for (int i=1;i<=n;i++)
f=f*i;
return f;
}
4.5题
#include
#include
using namespace std;
int

main()
{double e(double);
double x,sinh;
cout<<"enter x:";
cin>>x;
sinh=(e(x)+e(-x))/2;
cout<<"sinh("<return 0;
}

double e(double x)
{return exp(x);}



4.6题
#include
#include
using namespace std;
int main()
{double solut(double ,double ,double ,double );
double a,b,c,d;
cout<<"input a,b,c,d:";
cin>>a>>b>>c>>d;
cout<<"x="<return 0;
}

double solut(double a,double b,double c,double d)
{double x=1,x0,f,f1;
do
{x0=x;
f=((a*x0+b)*x0+c)*x0+d;
f1=(3*a*x0+2*b)*x0+c;
x=x0-f/f1;
}
while(fabs(x-x0)>=1e-5);
return(x);
}
4.7题
#include
#include
using namespace std;
int main()
{void godbaha(int);
int n;
cout<<"input n:";
cin>>n;
godbaha(n);
return 0;
}
void godbaha(int n)
{int prime(int);
int a,b;
for(a=3;a<=n/2;a=a+2)
{if(prime(a))
{b=n-a;
if (prime(b))
cout<}
}

int prime(int m)
{int i,k=sqrt(m);
for(i=2;i<=k;i++)
if(m%i==0) break;
if (i>k) return 1;
else return 0;
}


4.8题
#include
using namespace std;
int main()
{int x,n;
float p(int,int);
cout<<"input n & x:";
cin>>n>>x;
cout<<"n="<cout<<"P"<return 0;
}

float p(int n,int x)
{if (n==0)
return(1);
else if (n==1)
return(x);
else
return(((2*n-1)*x*p((n-1),x)-(n-1)*p((n-2),x))/n);
}

4.9题
#include
using namespace std;
int main()
{void hanoi(int n,char one,char two,char three);
int m;
cout<<"input the number of diskes:";
cin>>m;
cout<<"The steps of moving "<hanoi(m,'A','B','C');
return 0;
}

void hanoi(int n,char one,char two,char three)
//将n个盘从one座借助two座，移到three座
{void move(char x,char y);
if(n==1) move(one,three);
else
{hanoi(n-1,one,three,two);
move(one,three);
hanoi(n-1,two,one,three);
}
}

void move(char x,char y)
{cout<"<4.10题
#include
using namespace std;
int main()
{void convert(int n);
int number;
cout<<"input an integer:";
cin>>number;
cout<<"output:"<if (number<0)
{cout<<"-";
number=-number;
}
convert(number);
cout<return 0;
}

void convert(int n)
{int i;
char c;
if ((i=n/10)!=0)
convert(i);
c=n%10+'0';
cout<<" "<}

4.11题
#include
using namespace std;
int main()
{int f(int);
int n,s;
cout<<"input the number n:";
cin>>n;
s=f(n);
cout<<"The result is "<return 0;
}

int f(int n)
{;
if (n==1)
return 1;
else
return (n*n+f(n-1));
}



4.12题
#include
#include
using namespace std;
#define S(a,b,c) (a+b+c)/2
#define AREA(a,b,c) sqrt(S(a,b,c)*(S(a,b,c)-a)*(S(a,b,c)-b)*(S(a,b,c)-c))
int main()

{float a,b,c;
cout<<"input a,b,c:";
cin>>a>>b>>c;
if (a+b>c && a+c>b && b+c>a)
cout<<"area="<else
cout<<"It is not a triangle!"<return 0;
}

4.14题
#include
using namespace std;
//#define LETTER 1
int main()
{char c;
cin>>c;
#if LETTER
if(c>='a' && c<='z')
c=c-32;
#else
if(c>='A' && c<='Z')
c=c+32;
#endif
cout<return 0;
}

4.15题
#include
using namespace std;
#define CHANGE 1
int main()
{char ch[40];
cout<<"input text:"<gets(ch);
#if (CHANGE)
{for (int i=0;i<40;i++)
{if (ch[i]!='\0')
if (ch[i]>='a'&& ch[i]<'z'||ch[i]>'A'&& ch[i]<'Z')
ch[i]+=1;
else if (ch[i]=='z'||ch[i]=='Z')
ch[i]-=25;
}
}
#endif
cout<<"output:"<return 0;
}
4.16题file
#include
using namespace std;
int a;
int main()
{extern int power(int);
int b=3,c,d,m;
cout<<"enter an integer a and its power m:"<cin>>a>>m;
c=a*b;
cout<d=power(m);
cout<return 0;
}
4.16题file
extern int a;
int power(int n)
{int i,y=1;
for(i=1;i<=n;i++)
y*=a;
return y;
}
===============================================================================================

5.1题
#include
#include
using namespace std;
#include
int main()
{int i,j,n,a[101];
for (i=1;i<=100;i++)
a[i]=i;
a[1]=0;
for (i=2;ifor (j=i+1;j<=100;j++)
{if(a[i]!=0 && a[j]!=0)
if (a[j]%a[i]==0)
a[j]=0; }
cout<for (i=1,n=0;i<=100;i++)
{if (a[i]!=0)
{cout<n++;}
if(n==10)
{cout<n=0;}
}
cout<return 0;
}

5.2题
#include
using namespace std;
//#include
int main()
{int i,j,min,temp,a[11];
cout<<"enter data:"<for (i=1;i<=10;i++)
{cout<<"a["<cin>>a[i]; //输入10个数
}
cout<for (i=1;i<=10;i++)
cout<cout<for (i=1;i<=9;i++) //以下8行是对10个数排序
{min=i;
for (j=i+1;j<=10;j++)
if (a[min]>a[j]) min=j;
temp=a[i]; //以下3行将a[i+1]～a[10]中最小者与a[i] 对换
a[i]=a[min];
a[min]=temp;
}
cout<for (i=1;i<=10;i++) // 输出已排好序的10个数
cout<cout<return 0;
}

5.3题
#include
using namespace std;
int main()
{int a[3][3],sum=0;
int i,j;
cout<<"enter data:"<for (i=0;i<3;i++)
for (j=0;

j<3;j++)
cin>>a[i][j];
for (i=0;i<3;i++)
sum=sum+a[i][i];
cout<<"sum="<return 0;
}
5.4题
#include
using namespace std;
int main()
{int a[11]={1,4,6,9,13,16,19,28,40,100};
int num,i,j;
cout<<"array a:"<for (i=0;i<10;i++)
cout<cout<cout<<"insert data:";
cin>>num;
if (num>a[9])
a[10]=num;
else
{for (i=0;i<10;i++)
{if (a[i]>num)
{for (j=9;j>=i;j--)
a[j+1]=a[j];
a[i]=num;
break;
}
}
}
cout<<"Now, array a:"<for (i=0;i<11;i++)
cout<cout<return 0;
}
5.5题
#include
using namespace std;
int main()
{ const int n=5;
int a[n],i,temp;
cout<<"enter array a:"<for (i=0;icin>>a[i];
cout<<"array a:"<for (i=0;icout<for (i=0;i{ temp=a[i];
a[i]=a[n-i-1];
a[n-i-1]=temp;
}
cout<for (i=0;icout<cout<return 0;
}

5.6题
#include
#include
using namespace std;
int main()
{const int n=11;
int i,j,a[n][n];
for (i=1;i{a[i][i]=1;
a[i][1]=1;
}
for (i=3;ifor (j=2;j<=i-1;j++)
a[i][j]=a[i-1][j-1]+a[i-1][j];
for (i=1;i{for (j=1;j<=i;j++)
cout<cout<}
cout<return 0;
}
5.7题
#include
using namespace std;
int main()
{ const int n=4,m=5; //假设数组为4行5列
int i,j,a[n][m],max,maxj;
bool flag;
for (i=0;ifor (j=0;jcin>>a[i][j];
for (i=0;i{max=a[i][0]; maxj=0;
for (j=0;jif (a[i][j]>max)
{max=a[i][j]; //将本行的最大数存放在max中
maxj=j; //将最大数所在的列号存放在maxj中
}
flag=true; //先假设是鞍点，以flag为真代表
for (int k=0;kif (max>a[k][maxj]) //将最大数和其同列元素相比
{flag=false; //如果max不是同列最小，表示不是鞍点令flag1为
假
continue;}
if(flag) //如果flag1为真表示是鞍点
{cout<<"a["<//输出鞍点的值和所在行列号
break;
}
}
if(!flag) //如果flag为假表示鞍点不存在
cout<<"It does not exist!"<return 0;
}

5.8题
#include
using namespace std;
int main()
{ const int n=7;
int i,number,top,bott,mid,loca,a[n];
bool flag=true,sign;
char c;
cout<<"enter data:"<cin>>a[0];
i=1;
while(i{cin>>a[i];
if (a[i]>=a[i-1])

i++;
else
cout<<"enter this data again:";
}
cout<for (i=0;icout<cout<while(flag)
{cout<<"input number to look for:";
cin>>number;
sign=false;
top=0; //top是查找区间的起始位置
bott=n-1; //bott是查找区间的最末位置
if ((numbera[n-1])) //要查的数不在查找区间内
loca=-1; // 表示找不到
while ((!sign) && (top<=bott))
{mid=(bott+top)/2;
if (number==a[mid])
{loca=mid;
cout<<"Find "<sign=true;
}
else if (numberbott=mid-1;
else
top=mid+1;
}
if(!sign||loca==-1)
cout<cout<<"continu or not(Y/N)?";
cin>>c;
if (c=='N'||c=='n')
flag=false;
}
return 0;
}
5.9题
#include
using namespace std;
int main()
{int sum_day(int,int);
int leap(int year);
int year,month,day,days=0;
cout<<"input date(year,month,day):";
cin>>year>>month>>day;
cout<days=sum_day(month,day); /* 调用函数一
*/
if(leap(year) && month>=3) /* 调用函数二
*/
days=days+1;
cout<<" is the "<return 0;
}


int sum_day(int month,int day) //计算日期
{int i;
int day_tab[12]={31,28,31,30,31,30,31,31,30,31,30,31};
for (i=0;iday+=day_tab[i];
return(day);
}

int leap(int year) //判断是否为闰年
{int leap;
leap=year%4==0&&year%100!=0||year%400==0;
return(leap);
}

5.10题
#include
using namespace std;
int main()
{int i,j,upper,lower,digit,space,other;
char text[3][80];
upper=lower=digit=space=other=0;
for (i=0;i<3;i++)
{cout<<"please input line "<gets(text[i]);
for (j=0;j<80 && text[i][j]!='\0';j++)
{if (text[i][j]>='A'&& text[i][j]<='Z')
upper++;
else if (text[i][j]>='a' && text[i][j]<='z')
lower++;
else if (text[i][j]>='0' && text[i][j]<='9')
digit++;
else if (text[i][j]==' ')
space++;
else
other++;
}
}
cout<<"upper case:"<cout<<"lower case:"<cout<<"digit :"<cout<<"space :"<cout<<"other :"<return 0;
}
5.11题
#include
using namespace std;
int main()
{ char a[5]={'*','*','*','*','*'};
int i,j,k;
char space=' ';
for (i=0;i<5;i++) // 输出5行
{ cout<cout<<" "; // 每行前面留4个空格

for (j=1;j<=i;j++)
cout<for (k=0;k<5;k++)
cout<}
cout<return 0;
}
5.11题另一解
#include
#include
using namespace std;
int main()
{ string stars="*****";
int i,j;
for (i=0;i<5;i++) // 输出5行
{ cout<<" "; // 每行前面留4个空格
for (j=1;j<=i;j++)
cout<<" "; // 每行再插入i个空格
cout<}
return 0;
}
5.12题
#include
using namespace std;
int main()
{int j,n;
char ch[80],tran[80];
cout<<"input cipher code:";
gets(ch);
cout<<"cipher code:"<j=0;
while (ch[j]!='\0')
{ if ((ch[j]>='A') && (ch[j]<='Z'))
tran[j]=155-ch[j];
else if ((ch[j]>='a') && (ch[j]<='z'))
tran[j]=219-ch[j];
else
tran[j]=ch[j];
j++;
}
n=j;
cout<<"original text:";
for (j=0;jputchar(tran[j]);
cout<return 0;
}

5.12题另一解
#include
using namespace std;
int main()
{int j,n;
char ch[80];
cout<<"input cipher code:";
gets(ch);
cout<<"cipher code:"<j=0;
while (ch[j]!='\0')
{ if ((ch[j]>='A') && (ch[j]<='Z'))
ch[j]=155-ch[j];
else if ((ch[j]>='a') && (ch[j]<='z'))
ch[j]=219-ch[j];
else
ch[j]=ch[j];
j++;
}
n=j;
cout<<"original text:";
for (j=0;jputchar(ch[j]);
cout<return 0;
}


5.12另一解
#include
#include
using namespace std;
int main()
{int j;
string ch="I will visit China next week.",tran;
tran=ch;
cout<<"cipher code:"<j=0;
while (j<=ch.size())
{ if ((ch[j]>='A') && (ch[j]<='Z'))
tran[j]=155-ch[j];
else if ((ch[j]>='a') && (ch[j]<='z'))
tran[j]=219-ch[j];
else
tran[j]=ch[j];
j++;
}
cout<<"original text:";
cout<return 0;
}


5.12另一解
#include
#include
using namespace std;
int main()
{int j;
string ch="I will visit China next week.";
cout<<"cipher code:"<j=0;
while (j<=ch.size())
{ if ((ch[j]>='A') && (ch[j]<='Z'))
ch[j]=155-ch[j];
else if ((ch[j]>='a') && (ch[j]<='z'))
ch[j]=219-ch[j];
j++;
}
cout<<"original text:";
cout<return 0;
}


#include
#include
using namespace std;
int main()
{int j;
string ch="I will visit China next week.";
cout<<"cipher code:"<j=0;
while (j<=ch.size())
{ if ((ch[j]>='A') && (ch[j]<='Z'))
ch[j]=155-ch[j];
else if ((ch[j]>='a') && (ch[j]<='z'))
ch[j]=219-ch[j];
j++;
}
cout<<"original text:";
cout<return 0;
}


5.13题
#include
#include
using namespace st

d;
int main()
{char s1[80],s2[40];
int i=0,j=0;
cout<<"input string1:";
cin>>s1;
cout<<"input string2:";
cin>>s2;
while (s1[i]!='\0')
i++;
while(s2[j]!='\0')
s1[i++]=s2[j++];
s1[i]='\0';
cout<<"The new string is:"<return 0;
}

5.13另一解
#include
using namespace std;
int main()
{char s1[80],s2[40];
cout<<"input string1:";
cin>>s1;
cout<<"input string2:";
cin>>s2;
strcat(s1,s2);
cout<<"The new string is:"<return 0;
}
5.13另一解
#include
#include
using namespace std;
int main()
{ string s1="week",s2="end";
cout<<"s1="<cout<<"s2="<s1=s1+s2;
cout<<"The new string is:"<return 0;
}


5.14题
#include
#include
using namespace std;
int main()
{ const int n=5;
int i,j;
string str[n],temp;
cout<<"please input strings:"<for(i=0;icin>>str[i];
for(i=0;ifor(j=0;jif(str[j]>str[j+1])
{temp=str[j];str[j]=str[j+1];str[j+1]=temp;}
cout<for(i=0;icout<return 0;
}


5.15题
#include
#include
using namespace std;
int main()
{ const int n=5;
string str;
for(int i=0;i{cout<<"please input string:";
cin>>str;
if(str[0]=='A')
cout<return 0;
}



5.16题
#include
using namespace std;
int main()
{ const n=10;
int i;
char a[n],temp;
cout<<"please input a string:";
for(i=0;icin>>a[i];
for(i=0;i{temp=a[i];a[i]=a[n-i-1];a[n-i-1]=temp;}
for(i=0;icout<cout<return 0;
}



5.16题另一解
#include
#include
using namespace std;
int main()
{ string a;
int i,n;
char temp;
cout<<"please input a string:";
cin>>a;
n=a.size();
for(i=0;i{temp=a[i];a[i]=a[n-i-1];a[n-i-1]=temp;}
cout<return 0;
}



5.17题
#include
#include
using namespace std;
const int n=10;
string name[n];
int num[n],score[n];
int main()
{int i;
void input_data();
input_data();
cout<for(i=0;iif(score[i]<60)
cout<return 0;
}

void input_data()
{int i;
for (i=0;i{cout<<"input name,number and score of student "<cin>>name[i]>>num[i]>>score[i];}
}



==========================================================================================

6.1题
#include
#include
using namespace std;
const int n=10;
string name[n];
int num[n],score[n];
int main()
{int i;
void input_data();
input_data();
cout<for(i=0;iif(score[i]<60)
co

ut<return 0;
}

void input_data()
{int i;
for (i=0;i{cout<<"input name,number and score of student "<cin>>name[i]>>num[i]>>score[i];}
}

6.2题
#include
#include
using namespace std;
int main()
{void swap(char *,char *);
char str1[20],str2[20],str3[20];
cout<<"input three line:"<gets(str1);
gets(str2);
gets(str3);
if(strcmp(str1,str2)>0) swap(str1,str2);
if(strcmp(str1,str3)>0) swap(str1,str3);
if(strcmp(str2,str3)>0) swap(str2,str3);
cout<cout<return 0;
}
void swap(char *p1,char *p2) /* 交换两个字符串 */
{char p[20];
strcpy(p,p1);strcpy(p1,p2);strcpy(p2,p);
}

6.2题另一解
#include
#include
using namespace std;
int main()
{void change(string &,string &);
string str1=" ",
str2=" ",
str3=" ";
char *p1=&str1[0],*p2=&str2[0],*p3=&str3[0];
cout<<"input three line:"<gets(p1);
gets(p2);
gets(p3);
if(str1>str2)change(str1,str2);
if(str1>str3)change(str1,str3);
if(str2>str3)change(str2,str3);
cout<cout<return 0;
}
void change(string &st1,string &st2) /* 交换两个字符串 */
{string st;
st=st1;st1=st2;st2=st;
}

6.3题
#include
using namespace std;
int main()
{ void input(int *number);
void max_min_value(int *number);
void output(int *number);
int number[10];
input(number); // 调用输入10个数的函数
max_min_value(number); // 调用交换函数
output(number); // 调用输出函数
return 0;
}

void input(int *number) // 输入10个数的函数
{int i;
cout<<"input 10 numbers:";
for (i=0;i<10;i++)
cin>>number[i];
}

void max_min_value(int *number) // 交换函数
{ int *max,*min,*p,temp;
max=min=number;
for (p=number+1;pif (*p>*max) max=p; // 将大数地址赋给 max
else if (*p<*min) min=p; // 将小数地址赋给 min
temp=number[0];number[0]=*min;*min=temp; // 将最小数与第一数交换
temp=number[9];number[9]=*max;*max=temp; // 将最小数与第一数交换
}

void output(int *number) // 输出函数
{int *p;
cout<<"now,they are: ";
for (p=number;pcout<<*p<<" ";
cout<return;
}
6.4题
#include
using namespace std;
int main()
{void move(int *array,int n,int m);
int number[20],n,m,i;
cout<<"how many numbers?"; // 询问共有多少个数
cin>>n;
cout<<"input "<

输入n个数
for (i=0;icin>>number[i];
cout<<"how many places do you want move?"; // 询问后移多少个位置
cin>>m;
move(number,n,m); //调用move 函数
cout<<"Now,they are:"<for (i=0;icout<cout<return 0;
}

void move(int *array,int n,int m) //使循环后移一次的函数
{int *p,array_end;
array_end=*(array+n-1);
for (p=array+n-1;p>array;p--)
*p=*(p-1);
*array=array_end;
m--;
if (m>0) move(array,n,m); //递归调用,当循环次数m减至为0时,停止调用
}

6.5题
#include
using namespace std;
int main()
{int i,k,m,n,num[50],*p;
cout<<"input number of person: n=";
cin>>n;
p=num;
for (i=0;i*(p+i)=i+1; // 以1至n为序给每个人编号
i=0; // i为每次循环时计数变量
k=0; // k为按1,2,3报数时的计数变量
m=0; // m为退出人数
while (m环体
{if (*(p+i)!=0) k++;
if (k==3) // 将退出的人的编号置为0
{*(p+i)=0;
k=0;
m++;
}
i++;
if (i==n) i=0; // 报数到尾后，i恢复为0
}
while(*p==0) p++;
cout<<"The last one is NO."<<*p<return 0;
}
6.6题
#include
using namespace std;
int main()
{int length(char *p);
int len;
char str[20];
cout<<"input string:";
cin>>str;
len=length(str);
cout<<"The length of string is "<return 0;
}
int length(char *p) //求字符串长度的函数
{int n;
n=0;
while (*p!='\0')
{n++;
p++;
}
return(n);
}

6.7题
#include
using namespace std;
int main()
{void copystr(char *,char *,int);
int m;
char str1[20],str2[20];
cout<<"input string:";
gets(str1);
cout<<"which character do you want begin to copy?";
cin>>m;
if (strlen(str1)cout<<"input error!"<else
{copystr(str1,str2,m);
cout<<"result:"<}
return 0;
}

void copystr(char *p1,char *p2,int m) //字符串部分复制函数*/
{int n;
n=0;
while (n{n++;
p1++;
}
while (*p1!='\0')
{*p2=*p1;
p1++;
p2++;
}
*p2='\0';
}
6.8题
#include
using namespace std;
int main()
{int upper=0,lower=0,digit=0,space=0,other=0,i=0;
char *p,s[20];
cout<<"input string:";
while ((s[i]=getchar())!='\n') i++;
p=&s[0];
while (*p!='\n')
{if (('A'<=*p) && (*p<='Z'))
++upper;
else if (('a'<=*p) && (*p<='z'))
++lower;
else if (*p==' ')
++space;
else if ((*p<='9') && (*p>='0'))
++digit;
else
++other;
p++;
}
cout<<"upper case:"<cout<<"space:"<return 0

;
}

6.9题
#include
using namespace std;
int main()
{void move(int *);
int a[3][3],*p,i;
cout<<"input matrix:"<for (i=0;i<3;i++)
cin>>a[i][0]>>a[i][1]>>a[i][2];
p=&a[0][0];
move(p);
cout<<"Now,matrix:"<for (i=0;i<3;i++)
cout<cout<return 0;
}

void move(int *pointer)
{int i,j,t;
for (i=0;i<3;i++)
for (j=i;j<3;j++)
{t=*(pointer+3*i+j);
*(pointer+3*i+j)=*(pointer+3*j+i);
*(pointer+3*j+i)=t;
}
}

6.10题
#include
using namespace std;
int main()
{void change(int *p);
int a[5][5],*p,i,j;
cout<<"input matrix:"<for (i=0;i<5;i++) //输入矩阵
for (j=0;j<5;j++)
cin>>a[i][j];
p=&a[0][0]; //使p指向0行0列元素
change(p); //调用函数，实现交换
cout<<"Now,matrix:"<for (i=0;i<5;i++) //输出已交换的矩阵
{for (j=0;j<5;j++)
cout<cout<}
return 0;
}

void change(int *p) //交换函数
{int i,j,temp;
int *pmax,*pmin;
pmax=p;
pmin=p;
for (i=0;i<5;i++) //找最大值和最小值的地址,并赋给 pmax,pmin
for (j=i;j<5;j++)
{if (*pmax<*(p+5*i+j)) pmax=p+5*i+j;
if (*pmin>*(p+5*i+j)) pmin=p+5*i+j;
}
temp=*(p+12); //将最大值与中心元素互换
*(p+12)=*pmax;
*pmax=temp;

temp=*p; //将最小值与左上角元素互换
*p=*pmin;
*pmin=temp;

pmin=p+1;
//将a[0][1]的地址赋给pmin，从该位置开始找最小的元素
for (i=0;i<5;i++) //找第二最小值的地址赋给 pmin
for (j=0;j<5;j++)
if (((p+5*i+j)!=p) && (*pmin > *(p+5*i+j))) pmin=p+5*i+j;
temp=*pmin; //将第二最小值与右上角元素互换
*pmin=*(p+4);
*(p+4)=temp;

pmin=p+1;
for (i=0;i<5;i++) //找第三最小值的地址赋给pmin
for (j=0;j<5;j++)
if(((p+5*i+j)!=(p+4)) && ((p+5*i+j)!=p) &&(*pmin>*(p+5*i+j))) pmin=p
+5*i+j;
temp=*pmin; // 将第三最小值与左下角元素互换
*pmin=*(p+20);
*(p+20)=temp;

pmin=p+1;
for (i=0;i<5;i++) // 找第四最小值的地址赋给pmin */
for (j=0;j<5;j++)
if (((p+5*i+j)!=p) &&((p+5*i+j)!=(p+4)) && ((p+5*i+j)!=(p+20)) &&
(*pmin>*(p+5*i+j)))
pmin=p+5*i+j;
temp=*pmin; //将第四最小值与右下角元素互换
*pmin=*(p+24);
*(p+24)=temp;
}

6.10题另一解
#include
using namespace std;
int main()
{void change(int *p);
int a[5][5],*p,i,j;
cout<<"input matrix:"<for (i=0;i<5;i++) //输入矩阵
for (j=0;j<5;j++)
cin>>a[i][j];
p=&a[0][0]; //使p指向0行0列元素
change(p);

//调用函数，实现交换
cout<<"Now,matrix:"<for (i=0;i<5;i++) //输出已交换的矩阵
{for (j=0;j<5;j++)
cout<cout<}
return 0;
}

void change(int *p) //交换函数
{int i,j,temp;
int *pmax,*pmin;
pmax=p;
pmin=p;
for (i=0;i<5;i++) //找最大值和最小值的地址,并赋给 pmax,pmin
for (j=i;j<5;j++)
{if (*pmax<*(p+5*i+j)) pmax=p+5*i+j;
if (*pmin>*(p+5*i+j)) pmin=p+5*i+j;
}
temp=*(p+12); //将最大值与中心元素互换
*(p+12)=*pmax;
*pmax=temp;

temp=*p; //将最小值与左上角元素互换
*p=*pmin;
*pmin=temp;

pmin=p+1;
//将a[0][1]的地址赋给pmin，从该位置开始找最小的元素
for (i=0;i<5;i++) //找第二最小值的地址赋给 pmin
for (j=0;j<5;j++)
{if(i==0 && j==0) continue;
if (*pmin > *(p+5*i+j)) pmin=p+5*i+j;
}
temp=*pmin; //将第二最小值与右上角元素互换
*pmin=*(p+4);
*(p+4)=temp;

pmin=p+1;
for (i=0;i<5;i++) //找第三最小值的地址赋给pmin
for (j=0;j<5;j++)
{if((i==0 && j==0) ||(i==0 && j==4)) continue;
if(*pmin>*(p+5*i+j)) pmin=p+5*i+j;
}
temp=*pmin; // 将第三最小值与左下角元素互换
*pmin=*(p+20);
*(p+20)=temp;

pmin=p+1;
for (i=0;i<5;i++) // 找第四最小值的地址赋给pmin
for (j=0;j<5;j++)
{if ((i==0 && j==0) ||(i==0 && j==4)||(i==4 && j==0)) continue;
if (*pmin>*(p+5*i+j)) pmin=p+5*i+j;
}
temp=*pmin; //将第四最小值与右下角元素互换
*pmin=*(p+24);
*(p+24)=temp;
}
6.11题
#include
using namespace std;
int main()
{void sort(char s[][6]);
int i;
char str[10][6];
cout<<"input 10 strings:"<for (i=0;i<10;i++)
cin>>str[i];
sort(str);
cout<<"Now,the sequence is:"<for (i=0;i<10;i++)
cout<return 0;
}

void sort(char s[][6])
{int i,j;
char *p,temp[10];
p=temp;
for (i=0;i<9;i++)
for (j=0;j<9-i;j++)
if (strcmp(s[j],s[j+1])>0)
{strcpy(p,s[j]);
strcpy(s[j],s[+j+1]);
strcpy(s[j+1],p);
}
}
6.11题另一解
#include
using namespace std;
int main()
{void sort(char (*p)[6]);
int i;
char str[10][6];
char (*p)[6];
cout<<"input 10 strings:"<for (i=0;i<10;i++)
cin>>str[i];
p=str;
sort(p);
cout<<"Now,the sequence is:"<for (i=0;i<10;i++)
cout<return 0;
}

void sort(char (*s)[6])
{int i,j;
char temp[6],*t=temp;
for (i=0;i<9;i++)
for (j=0;j<9-i;j++)
if (strcmp(s[j],s[j+1])>0)
{strcpy(t,s[j]);
strcpy(s[j],s[+j+1]);
strcpy(s[j+1],t);
}
}
6.11题另一解
#include
#include
using namespace std;
int main()
{void sort(string *);
int i;
string str[10],

*p=str;
cout<<"input 10 strings:"<for (i=0;i<10;i++)
cin>>str[i];
sort(p);
cout<<"Now,the sequence is:"<for (i=0;i<10;i++)
cout<return 0;
}

void sort(string *s)
{int i,j;
string temp;
for (i=0;i<9;i++)
for (j=0;j<9-i;j++)
if (s[j]>s[j+1])
{temp=s[j];
s[j]=s[+j+1];
s[j+1]=temp;
}
}
6.12题
#include
using namespace std;
int main()
{void sort(char *[]);
int i;
char *p[10],str[10][20];
for (i=0;i<10;i++)
p[i]=str[i]; //将第i个字符串的首地址赋予指针数组p的第i个元素
cout<<"input 10 strings:"<for (i=0;i<10;i++)
cin>>p[i];
sort(p);
cout<<"Now,the sequence is:"<for (i=0;i<10;i++)
cout<return 0;
}

void sort(char *s[])
{int i,j;
char *temp;
for (i=0;i<9;i++)
for (j=0;j<9-i;j++)
if (strcmp(*(s+j),*(s+j+1))>0)
{temp=*(s+j);
*(s+j)=*(s+j+1);
*(s+j+1)=temp;
}
}
6.13题
#include
#include
using namespace std;
int main()
{float integral(float (*p)(float),float a,float b,int n);
float a1,b1,a2,b2,a3,b3,c,(*p)(float);
float fsin(float); // 对fsin函数作声明
float fcos(float); // 对fcos函数作声明
float fexp(float); // 对fexp函数作声明
int n=20;
cout<<"input a1,b1:"; //输入求sin(x) 定积分的下限和上限
cin>>a1>>b1;
cout<<"input a2,b2:"; // 输入求cos(x) 定积分的下限和上限
cin>>a2>>b2;
cout<<"input a3,b3:"; // 输入求#include
cin>>a3>>b3;
p=fsin;
c=integral(p,a1,b1,n); // 求出sin(x)的定积分
cout<<"The integral of sin(x) is :"<p=fcos;
c=integral(p,a2,b2,n); // 求出cos(x)的 定积分
cout<<"The integral of cos(x) is :"<p=fexp;
c=integral(p,a3,b3,n); // 求出 的定积分
cout<<"The integral of exp(x) is :"<return 0;
}

float integral(float (*p)(float),float a,float b,int n)
//用矩形法求定积分的通用函数
{int i;
float x,h,s;
h=(b-a)/n;
x=a;
s=0;
for (i=1;i<=n;i++)
{x=x+h;
s=s+(*p)(x)*h;
}
return(s);
}

float fsin(float x) // 计算sin(x) 的函数
{return sin(x);}

float fcos(float x) // 计算cos(x) 的函数
{return cos(x);}

float fexp(float x) // 计算exp(x)的函数
{return exp(x);}
6.13题
#include
#include
using namespace std;
int main()
{float integral(float (*p)(float),float a,float b,int n);
float a1,b1,a2,b2,a3,b3,c,(*p)(float);
float fsin(float); // 对fsin函数作声明
float fcos(float); // 对fcos函数作声明
float fexp(float); // 对fexp函数作声明
int n=20;
cout<<"input a1,b1:"; //输入求sin(x) 定积分的下限

和上限
cin>>a1>>b1;
cout<<"input a2,b2:"; // 输入求cos(x) 定积分的下限和上限
cin>>a2>>b2;
cout<<"input a3,b3:"; // 输入求#include
cin>>a3>>b3;
p=fsin;
c=integral(p,a1,b1,n); // 求出sin(x)的定积分
cout<<"The integral of sin(x) is :"<p=fcos;
c=integral(p,a2,b2,n); // 求出cos(x)的 定积分
cout<<"The integral of cos(x) is :"<p=fexp;
c=integral(p,a3,b3,n); // 求出 的定积分
cout<<"The integral of exp(x) is :"<return 0;
}

float integral(float (*p)(float),float a,float b,int n)
//用矩形法求定积分的通用函数
{int i;
float x,h,s;
h=(b-a)/n;
x=a;
s=0;
for (i=1;i<=n;i++)
{x=x+h;
s=s+(*p)(x)*h;
}
return(s);
}

float fsin(float x) // 计算sin(x) 的函数
{return sin(x);}

float fcos(float x) // 计算cos(x) 的函数
{return cos(x);}

float fexp(float x) // 计算exp(x)的函数
{return exp(x);}

6.14题
#include
using namespace std;
int main()
{ void sort (char *p,int m);
int i,n;
char *p,num[20];
cout<<"input n:";
cin>>n;
cout<<"please input these numbers:"<for (i=0;icin>>num[i];
p=&num[0];
sort(p,n);
cout<<"Now,the sequence is:"<for (i=0;icout<cout<return 0;
}

void sort (char *p,int m) // 将n个数逆序排列函数
{int i;
char temp, *p1,*p2;
for (i=0;i{p1=p+i;
p2=p+(m-1-i);
temp=*p1;
*p1=*p2;
*p2=temp;
}
}

6.15题
#include
using namespace std;
int main()
{void avsco(float *,float *);
void avcour1(char (*)[10],float *);
void fali2(char course[5][10],int num[],float *pscore,float aver[4]);
void good(char course[5][10],int num[4],float *pscore,float aver[4]);
int i,j,*pnum,num[4];
float score[4][5],aver[4],*pscore,*paver;
char course[5][10],(*pcourse)[10];
cout<<"input course:"<pcourse=course;
for (i=0;i<5;i++)
cin>>course[i];
cout<<"input NO. and scores:"<cout<<"NO.";
for (i=0;i<5;i++)
cout<<","<cout<pscore=&score[0][0];
pnum=&num[0];
for (i=0;i<4;i++)
{cin>>*(pnum+i);
for (j=0;j<5;j++)
cin>>*(pscore+5*i+j);
}
paver=&aver[0];
cout<avsco(pscore,paver); // 求出每个学生的平均成绩
avcour1(pcourse,pscore); // 求出第一门课的平均成绩
cout<fali2(pcourse,pnum,pscore,paver); // 找出两门课不及格的学生
cout<good(pcourse,pnum,pscore,paver); // 找出成绩好的学生
return 0;
}

void avsco(float *pscore,float *paver) // 求每个学生的平均成绩的函数
{int i,j;
float sum,average;
for (i=0;i<4;i++)
{sum=0.0;
for (j=0;j<5;j++)

sum=sum+(*(pscore+5*i+j)); //累计每个学生的各科成绩
average=sum/5; //计算平均成绩
*(paver+i)=average;
}
}

void avcour1(char (*pcourse)[10],float *pscore) // 求第一课程的平均成
绩的函数
{int i;
float sum,average1;
sum=0.0;
for (i=0;i<4;i++)
sum=sum+(*(pscore+5*i)); //累计每个学生的得分
average1=sum/4; //计算平均成绩
cout<<"course 1: "<<*pcourse<<",average score:"<}

void fail2(char course[5][10],int num[],float *pscore,float aver[4])
// 找两门以上课程不及格的学生的函数
{int i,j,k,labe1;
cout<<" ==========Student who failed in two courses ======= "<cout<<"NO. ";
for (i=0;i<5;i++)
cout<cout<<" average"<for (i=0;i<4;i++)
{labe1=0;
for (j=0;j<5;j++)
if (*(pscore+5*i+j)<60.0) labe1++;
if (labe1>=2)
{cout<for (k=0;k<5;k++)
cout<<*(pscore+5*i+k)<<" ";
cout<<" "<}
}
}

void good(char course[5][10],int num[4],float *pscore,float aver[4])
// 找成绩优秀学生(全部课程成绩在85分以上或平均成绩在90分以上)的函数
{int i,j,k,n;
cout<<" ======Students whose score is good======"<cout<<"NO. ";
for (i=0;i<5;i++)
cout<cout<<" average"<for (i=0;i<4;i++)
{n=0;
for (j=0;j<5;j++)
if (*(pscore+5*i+j)>85.0) n++;
if ((n==5)||(aver[i]>=90))
{cout<for (k=0;k<5;k++)
cout<<*(pscore+5*i+k)<<" ";
cout<<" "<}
}
}


6.16题
#include
using namespace std;
int main()
{char str[50],*pstr;
int i,j,k,m,e10,digit,ndigit,a[10],*pa;
cout<<"input a string:"<gets(str);
cout<pstr=&str[0]; //字符指针pstr指向数组str首元素
pa=&a[0]; //指针pa指向a数组首元素
ndigit=0; //ndigit代表有多少个整数
i=0; //i代表字符串中的第几个字符/
j=0; //j代表连续数字的位数
while(*(pstr+i)!='\0')
{if((*(pstr+i)>='0') && (*(pstr+i)<='9'))
j++;
else
{if (j>0)
{digit=*(pstr+i-1)-48; //将个数位赋予digit
k=1;
while (k{e10=1;
for (m=1;m<=k;m++)
e10=e10*10; //e10代表该位数所应乘的因子
digit=digit+(*(pstr+i-1-k)-48)*e10; //将该位数的数值累加于digit
k++; //位数k自增
}
*pa=digit; //将数值放在数组a中
ndigit++;
pa++; //指针pa指向a数组下一元素
j=0;
}
}
i++;
}
if (j>0) //以数字结尾字