/**
作者:程鹏远
题目:30道2年纪四则运算题目
要求:减法结果不为负数,除法能整除,除数不为0;
*/
#include <iostream.h>
#include <stdlib.h>
int main()
{
	int a,b,c;
	for(int i=0;i<30;i++)
	{
		cout<<"第"<<i+1<<"题: ";
		a=rand()%100;//x+rand()%(y-x+1)随机生成【x,y】内的整数
		b=rand()%100;
		c=rand()%4;
		switch (c)
		{
		case 1:
			cout<<a<<"+"<<b<<"="<<endl;
			break;
		case 2:
			if(a>b){cout<<a<<"-"<<b<<"="<<endl;}
			else{cout<<b<<"-"<<a<<"="<<endl;}
			break;
		case 3:			
			cout<<a<<"*"<<b<<"="<<endl;
			break;
		case 0:	
			
			int j=0;
			while((j<100000)&&(a!=0)&&(b!=0)&&(a%b==0)){cout<<a<<"/"<<b<<"="<<endl;i++;j++;}
		
			if((a!=0)&&(b!=0)&&(a%b==0)){cout<<a<<"/"<<b<<"="<<endl;i++;}
			else{
				int j=0;
				while(j<100000)
				{
					a=rand()%1000;//x+rand()%(y-x+1)随机生成【x,y】内的整数
					b=rand()%100;
					if((a!=0)&&(b!=0)&&(a%b==0)){cout<<a<<"/"<<b<<"="<<endl;i++;j=100000;j++;}
					else{j++;}
				}
			}
		
			break;	
		}	
	}
	return 0;
}
原文:http://www.cnblogs.com/zhaixing/p/4319704.html