#include <iostream>

#include <cstdio>

#include <ctime>

int main() {

    std::clock_t start;

    double duration;

    start = std::clock();

    int i, sum;

    for(i=1; i<100000000; i++){

      sum+=i;

    }

    /* Your algorithm here */

    duration = ( std::clock() - start ) / (double) CLOCKS_PER_SEC;

    std::cout<<"printf: "<< duration <<'\n';

}