assignbench.c

#include <stdio.h>
#include <time.h>
#define REP 200000000

double kybos1(float);
double ginomeno1(float,float,float);
double kybos2(float);
double ginomeno2(float,float,float);

int main() {
    clock_t begin1, end1,begin2, end2;
    double time_spent1, time_spent2;
    float x,y,z;
    double fu = 0;
    int i;
    
    begin1 = clock();
    for (i = 0; i < REP; i++){
        x = y = z = i;
        // Γίνεται πρόσθεση στην fu ώστε να μην αγνοήσει την πράξη ο compiler
        // (αφού διαφορετικά δεν θα υπάρχει αποτέλεσμα που πρέπει να
        // εμφανιστεί, άρα δεν υπάρχει λόγος να γίνει η πράξη)
        fu += kybos1(x) + ginomeno1(x,y,z);
    }
    
    end1 = clock();
    printf("fu 1 = %lf\n",fu);
    time_spent1 = (double) (end1 - begin1) / CLOCKS_PER_SEC;
    
    fu = 0;
    begin2 = clock();
    for (i = 0; i < REP; i++){
        x = y = z = i;
        fu += kybos2(x) + ginomeno2(x,y,z);
    }
    
    end2 = clock();
    printf("fu 2 = %lf\n",fu);
    time_spent2 = (double) (end2 - begin2) / CLOCKS_PER_SEC;
    
    printf("Time 1 = %lf\nTime 2 = %lf\n", time_spent1, time_spent2);
    return 0;
}

double kybos1(float x) {
    return x*x*x;
}

double ginomeno1(float x, float y, float z) {
    return x*y*z;
}

double kybos2(float x) {
    double t;
    t=x*x*x;
    return t;
}

double ginomeno2(float x, float y, float z) {
    double t;
    t=x*y*z;
    return t;
}