C++ 定时计算/*麻烦看下怎么加东西，让程序可以定时结束*/

[梦想一米七八]

#include <iostream>
#include "stdlib.h"
#define MAX 100
#include "time.h"
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
char suanfa(int n){
switch(n){
case 0:return '+';
case 1:return '-';
case 2:return '*';
case 3:return '/';
}
}
int main(int argc, char** argv) {
time_t tt = time(NULL);
tm* t= localtime(&tt);
printf("%d-%02d-%02d %02d:%02d:%02d\n", //得到当前时间
t->tm_year + 1900,
t->tm_mon + 1,
t->tm_mday,
t->tm_hour,
t->tm_min,
t->tm_sec);

srand((unsigned)time(NULL));//随机题目不重复
int number1,number2;int i;int count=0;
float user_answer,right_answer;
int operators;
for(i=1;i<=MAX;i++){
number1=rand()%100;
number2=rand()%100;
operators=rand()%4;
cout<<i<<":"<<number1<<suanfa(operators)<<number2<<"=";
cin>>user_answer;
switch(operators){
case 0:right_answer=number1+number2;break;
case 1:right_answer=number1-number2;break;
case 2:right_answer=number1*number2;break;
case 3:right_answer=number1/number2;break;
}
if(right_answer==user_answer){
cout<<"you are right."<<endl;
count++;
}
else
cout<<"you are wrong."<<endl;
}


cout<<count<<"/"<<(i-1);/*准确率*/
return 0;
}

[赵4老师]

#include <iostream>
#include "stdlib.h"
#define MAX 10
#include "time.h"
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
char suanfa(int n) {
    switch(n) {
    case 0:return '+';
    case 1:return '-';
    case 2:return '*';
    case 3:return '/';
    }
}
int main(int argc, char** argv) {
    time_t tt = time(NULL),te=tt+60;
    tm* t= localtime(&tt);
    printf("%d-%02d-%02d %02d:%02d:%02d\n",     //得到当前时间
           t->tm_year + 1900,
           t->tm_mon + 1,
           t->tm_mday,
           t->tm_hour,
           t->tm_min,
           t->tm_sec);

    srand((unsigned)time(NULL));//随机题目不重复
    int number1,number2;int i;int count=0;
    float user_answer,right_answer;
    int operators;
    int td;
    for(i=1;i<=MAX;i++) {
        number1=rand()%100;
        number2=rand()%100;
        operators=rand()%4;
        td=int(te-time(NULL));
        if (td>0) {
            cout<<"You have "<<td<<" second(s)!"<<endl;
        } else {
            cout<<"60s timeover!"<<endl;
            break;
        }
        cout<<i<<":"<<number1<<suanfa(operators)<<number2<<"=";
        cin>>user_answer;
        if (time(NULL)>te) {
            cout<<"60s timeover!"<<endl;
            break;
        }
        switch(operators) {
        case 0:right_answer=number1+number2;break;
        case 1:right_answer=number1-number2;break;
        case 2:right_answer=number1*number2;break;
        case 3:right_answer=number1/number2;break;
        }
        if(right_answer==user_answer) {
            cout<<"you are right."<<endl;
            count++;
        } else
            cout<<"you are wrong."<<endl;
    }


    cout<<count<<"/"<<(i-1);/*准确率*/
    return 0;
}

[@风轻云淡_]

你既然已经获取到了当前时间，加个循环，让时间作为循环的唯一出口，比如多少分钟后程序结束，或者哪个时刻程序结束不就可以了吗。而至于需要把哪些代码放到循环里面，哪些在外面，相信你自己可以做好。