四则运算

实现随机出题进行测验

#include <stdio.h> 
#include <ctype.h>
#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include <windows.h>
#define IDNO_LENGTH 6
#define CALC_KIND 4

char getSignal();
int getResult(int,int,char);
void takeTest();
void falsePrint(int);
void correctPrint(int);


int main()
{
    while(1)
    {
        takeTest();    
    }
}

char getSignal()                        //随机运算符
{
    char signal[CALC_KIND]={'+','-','*','/'};
    srand((unsigned)time(NULL));
    return signal[rand()%4];
}


int random(double start, double end)    //获取随机数
{
    return (int)(start+(end-start)*rand()/(RAND_MAX+ 1.0));
}

int getResult(int num1,int num2,char signal)    //进行题目运算
{
    int res;
    switch(signal)
    {
        case '+':
        res=num1+num2;break;
        case '-':
        res=num1-num2;break;
        case '*':
        res=num1*num2;break;
        case '/':
        res=num1/num2;break;
        default:res=0;break;
    }
    return res;
}


void takeTest()
{
    int giveRes,num1,num2,printFlag;
    char signal;
    srand((unsigned)time(NULL));
    signal=getSignal();
    num1=random(0,100);
    num2=random(1,100);
    
    if(signal=='-')                            //确保减法出现负数
    {
        if(num1<num2)
        {
            int temp;
            temp=num1;
            num1=num2;
            num2=temp;
        }
    }
    
    if(signal=='/')                            //防止除法运算出现除数为零
    {
        if(num2==0)
        {
            int temp;
            temp=num1;
            num1=num2;
            num2=temp;
        }
    }
}