func_clock

clockfunc.cpp

#include <iostream>
#include <unistd.h>

using namespace std;

#define T(f) do { \
	time_t start = clock(); \
	f; \
	cout << #f << " running time is " <<float(clock()-start)/CLOCKS_PER_SEC<<" s"<<endl; \
}while (0)

void function_a(int a){
	long product;
	for(int i=0; i<a; i++){
		for(int j=0; j<a; j++){
					product = i*j;
		}
	}
}

int main(int argc, char *argv[]) {
	T(function_a(1000));
	T(function_a(10000));
}