头文件添加
#include <time.h>
int main()
{
int i, j;
clock_t start, finish;
start = clock();
//添加程序块
finish = clock();
printf("\n本次计算一共耗时:%f秒\n\n", (double)(finish-start)/CLOCKS_PER_SEC);
return 0;
}原文：http://blog.csdn.net/u012421537/article/details/44889113