计算时间差

#include<ctime>
#include<iostream>
using namespace std;

void fun()
{
	int test = 0;
	for(int i=0;i<10000;i++){
		for(int j=0;j<10000;j++){
			test++;
		}
	}
}
int main()
{
	clock_t start = clock();
	fun();
	clock_t end = clock();
	double elapse = double(end-start)/CLOCKS_PER_SEC;//CLOCKS_PER_SEC:1000000
	cout << elapse << endl;
}

0.28 //gcc