/*
  Program to measure time to initialize a nxn matrix to a value.
  a(i,j) = 1 for i=1,...,n, and j=1,...,n.
 */

#include <stdio.h>
#include <time.h>
int main()
{
  int i, j;
  printf("Matrix size    Elapsed time [sec] \n");

  for (int k=1; k<=30; k++) {
    // Matrix size
    int n = k*1000;

    // Allocation
    int **a;
    a = new int*[n];
    for (i=0; i<n; i++)
      a[i] = new int[n];

    // Start time
    clock_t time0 = clock();

    // Main calculation: initialization
    for (i=0; i<n; i++)
      for (j=0; j<n; j++)
	a[i][j] = 1;

    // Finish time
    clock_t time1 = clock();

    // Output time
    double time = (double)(time1-time0)/CLOCKS_PER_SEC;
    printf("%11d %15.7f\n",n, time);

    // Deallocation
    for (int i=0; i<n; i++)
      delete[] a[i];
    delete[] a;
  }
  return 0;
}