例4.1
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
int a[10];
int i;
for(i = 0;i<10;i++)
a[i] = i*2+2;
for(i = 0;i<10;i++)
{
cout<<a[i]<<'\t';
if((i + 1)%5 == 0 )
cout<<endl;
}
return 0;
}
例4.2
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
int i, math[40], n;
float aver = 0.0;
int unpassedcount = 0;
int highscorecount = 0;
cout<<"请输入学生人数：";
cin>>n;
cout<<"请输入成绩：" ;
for(i = 0;i<n;i++)
{
cin>>math[i];
aver += math[i];
}
aver /= n;
for(i = 0;i<n;i++)
{
if(math[i]<60)
unpassedcount++;
if(math[i]>=90)
highscorecount++;
}
cout<<"平均分位："<<aver<<endl;
cout<<"90分以上人数为："<<highscorecount<<endl;
cout<<"不及格人数为："<<unpassedcount<<endl;
return 0;
}
例4.3
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int a[10], i, big;
cout<<"Please input 10 number:\n";
for(i = 0;i<10;i++)
cin>>a[i];
cout<<"the numbers are: ";
for(i = 0;i<10;i++)
cout<<setw(4)<<a[i];
cout<<endl;
big = a[0];
for(i = 0;i<10;i++)
if(a[i]>big)
big = a[i];
cout<<"the big number is: "<<big<<endl;
return 0;
}
例4.4
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int a[10];
int i, j, t;
cout<<"Please input 10 number:\n";
for(i = 0;i<10;i++)
cin>>a[i];
cout<<"the numbers are: ";
for(i = 0;i<10;i++)
cout<<setw(4)<<a[i];
cout<<endl;
for(i = 0;i<10;i++)
for(j = 0;j<9-i;j++)
if(a[j]>a[j+1])
{
t = a[j], a[j] = a[j+1], a[j+1] = t;
}
cout<<"the sorted numbers are: ";
for(i = 0;i<10;i++)
cout<<setw(4)<<a[i];
cout<<endl;
return 0;
}
例4.5
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int i;
int f[40] = {1,1};
for(i = 2;i<40;i++)
{
f[i] = f[i-2]+f[i-1];
}
for(i = 0;i<40;i++)
{
if(i%4 == 0)
{
cout<<endl;
}
cout<<setw(12)<<f[i];
}
cout<<endl;
return 0;
}
例4.6
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int i;
int j;
int a[5][5];
for(i = 0;i<5;i++)
{
for(j = 0;j<5;j++)
{
if(i%2==0)
a[i][j] = i*5+j+1;
else
a[i][4-j] = i*5+j+1;
}
}
for(i = 0;i<5;i++)
{
for(j = 0;j<5;j++)
cout<<setw(4)<<a[i][j];
cout<<endl;
}
return 0;
}
例4.7
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
int i, j, t, n, m;
int a[2][3];
cout<<"请输入二维数组的元素值:"<<endl;
for(i = 0;i<2;i++)
{
for(j = 0;j<3;j++)
{
cout<<"a"<<"["<<i<<"]"<<"["<<j<<"] = ";
cin>>a[i][j];
}
}
cout<<"该二维数组为："<<endl;
t = a[0][0];
for(i = 0;i<2;i++)
{
for(j = 0;j<3;j++)
{
cout<<setw(4)<<a[i][j];
if(a[i][j]>t)
{
t = a[i][j];
n = i, m = j;
}
}
cout<<endl;
}
cout<<"该数组中最大的元素值为："<<"a"<<"["<<n<<"]"<<"["<<m<<"] = "<<t<<endl;
return 0;
}
例4.8
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
char str[50];
cout<<"Please input string: ";
cin.get (str,50);
cout<<"The string is: ";
cout<<str<<endl;
return 0;
}
例4.9
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
char str[100];
cout<<"Please input string: ";
cin.get (str,100);
cout<<"字符串"<<str<<"的反向字符串为：";
for(int i = strlen(str)-1;i>=0;i--)
cout<<str[i];
cout<<endl;
return 0;
}
例4.10
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
char s[] = "The is C programming test.";
int i = 0, pLen = 0, maxLen = 0, pSeat = 0;
while(s[i]!='\0')
{
while(s[i]!=' '&&s[i]!='\0')
{
pLen++;
i++;
}
if(pLen>maxLen)
{
pSeat = i - pLen;
maxLen = pLen;
}
while(s[i] == ' ')
i++;
pLen = 0;
}
cout<<"最长的单词为： ";
for(i = 0;i<maxLen;i++)
cout<<s[pSeat+i];
cout<<endl;
return 0;
}
例4.11
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
char str[50];
cout<<"Please input a string:";
cin.get (str,50);
cout<<"The length of sring"<<str<<"is"<<strlen(str)<<endl;
return 0;
}
例4.12
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
char str[10];
cout<<"请输入字符串，知道输入hello后程序结束："<<endl;
do
{
cin>>str;
}while(strcmp(str,"hello")!=0);
return 0;
}
例4.13
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
char str[50];
int len = 0;
cout<<"请输入一个字符串: "<<endl;
cin.get (str,50);
while(str[len]!='\0')
len++;
cout<<"字符串"<<str<<"的长度为："<<len<<endl;
return 0;
}
习题：
1.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
#include<iomanip>
using namespace std;
int main()
{
int a[5];
int i,j,t;
cout<<"请输入5个数字：";
for(i=0;i<5;i++)
cin>>a[i];
for(i=0;i<4;i++)
for(j=0;j<4-i;j++)
if(a[j]>a[j+1])
{
t=a[j];
a[j]=a[j+1];
a[j+1]=t;
}
cout<<"这些数字的正确排序是：";
for(i=0;i<5;i++)
cout<<setw(3)<<a[i];
cout<<endl;
return 0;
}
2.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
#include<iomanip>
using namespace std;
int main()
{
int a[2][3];
int i,j,big;
cout<<"请输入2行3列的数字值:"<<endl;
for(i=0;i<2;i++)
for(j=0;j<3;j++)
{
cout<<"a["<<i<<"]"<<"["<<j<<"]=";
cin>>a[i][j];
}
cout<<"这个二维数组是："<<endl;
for(i=0;i<2;i++)
{
for(j=0;j<3;j++)
cout<<setw(4)<<a[i][j];
cout<<endl;
}
big=a[0][0];
for(i=0;i<2;i++)
{
for(j=0;j<3;j++)
if(a[i][j]>big)
big=a[i][j];
}
for(i=0;i<2;i++)
for(j=0;j<3;j++)
if(a[i][j]==big)
cout<<"该数组的最大值为："<<"a["<<i<<"]"<<"["<<j<<"]="<<a[i][j]<<endl;
return 0;
}
3.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
using namespace std;
int function(int n);
int main()
{
int i,count;
count=0;
for(i=1;i<=20;i++)
{
cout<<function(i)<<" ";
cout<<endl;
if(function(i)>=100&&function(i)<=999)
count++;
}
cout<<"Fibonacci数列前20个数中的三位数个数为:"<<count<<endl;
cout<<"该数列第16项数据是:"<<function(16)<<endl;
return 0;
}
int function(int n)
{
if(n==1||n==2)return 1;
else return function(n-1)+function(n-2);
}
4.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
#include<iomanip>
using namespace std;
int main()
{
char a[100];
int i,xiaoxue=0,shuzi=0,daxue=0,kongge=0,qita=0;
cout<<"请输入一行字符小于100的文字:";
cin.get(a,100);
for(i=0;i<100;i++)
{
if(a[i]>='a'&&a[i]<='z')
xiaoxue++;
else if
(a[i]>='0'&&a[i]<='9') //因为a被定义为char,,所以应该写成'0' '9'
shuzi++;
else if
(a[i]>='A'&&a[i]<='Z')
daxue++;
else if
(a[i]==' ')
kongge++;
else if
(a[i]=='\0')
qita=strlen(a)-(shuzi+xiaoxue+daxue+kongge);
}
cout<<"数字个数为:"<<shuzi<<endl;
cout<<"小写字母个数为:"<<xiaoxue<<endl;
cout<<"大写字母个数为:"<<daxue<<endl;
cout<<"空格个数为:"<<kongge<<endl;
cout<<"其他字符个数为:"<<qita<<endl;
return 0;
}
5.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
#include<cstring>
using namespace std;
int main()
{
char str[100];
cout<<"请输入一个字符串:";
cin.get(str,100);
cout<<"字符串“"<<str<<"”的反向字符串为：";
for(int i=strlen(str)-1;i>=0;i--)
cout<<str[i];
cout<<endl;
cout<<"此字符串的长度为："<<strlen(str)<<endl;
return 0;
}
6.
// 1111.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include<iostream>
#include<iostream>
#include<cstring>
using namespace std;
int main()
{
char i,str[100],count=0;
cout<<"请输入一个字符串:";
cin.get(str,100);
cout<<"删除数字后的字符串为：";
for(i=0;i<100;i++)
{
if(str[i]=='\0')
break;
else if(str[i]>='0'&&str[i]<='9')
{
cout<<"\0";
count++;
}
else cout<<str[i];
}
cout<<endl;
cout<<"此字符串的长度为："<<strlen(str)-count<<endl;
return 0;
}