Problem: How to Measure the execution time of code or function speed in C++?
Language: C++ [CPP]
Solution: Use C++ clock() function to calculate elapsed time of code or function call
How to use clock() function to measure elapsed time?
Below example code is to calculate total elapsed time to execute an empty loop for 10000 times.
clock() prints the elapsed time in milliseconds.
To get it in seconds, you can use CLOCKS_PER_SEC macro
#include <iostream> #include <time.h> // header file for clock() function #include <stdio.h> // header file for printf() int main() { //declare start time clock_t start_time; // declare elapsed time, in milliseconds and seconds float elapsed_time_milli,elapsed_time_sec; int i; // C++ start time start_time=clock(); // for loop for(i=0;i<10000;i++); // C++ elapsed time calculation elapsed_time_milli=float(clock()-start_time); // print elapsed time in milliseconds printf("Time to do 10000 empty loops is %f milliseconds\n",elapsed_time_milli); // print elapsed time in seconds elapsed_time_sec=elapsed_time_milli/CLOCKS_PER_SEC; printf("Time to execute 10000 empty loops is %f seconds",elapsed_time_sec); }