README.md

Loops

A simple, not-super-useful program that does a total of 1 billion loop iterations, with some addition and mod operations for each. The idea with this is to emphasize loop, conditional, and basic math performance.

Below is the reference C program. All languages must do the same array work and computations outlined here.

#include "stdio.h"
#include "stdlib.h"
#include "stdint.h"
#include "time.h"

int main (int argc, char** argv) {     // EVERY PROGRAM IN THIS BENCHMARK MUST...
  int u = atoi(argv[1]);               // Get an single input number from the command line
  srand(time(NULL));
  int r = rand() % 10000;              // Get a single random integer 0 <= r < 10k
  int32_t a[10000] = {0};              // Create an array of 10k elements initialized to 0
  for (int i = 0; i < 10000; i++) {    // 10k outer loop iterations with an iteration variable
    for (int j = 0; j < 100000; j++) { // 100k inner loop iterations, per outer loop iteration, with iteration variable
      a[i] = a[i] + j%u;               // For all 1B iterations, must access array element, compute j%u, update array location
    }
    a[i] += r;                         // For all 10k outer iterations, add the random value to each element in array
  }
  printf("%d\n", a[r]);                // Print out a single element from the array
}