/*
** $Id: loop.c 819 2008-03-09 17:41:59Z phf $
**
** Example for performance impact of memory access
** patterns.
*/

enum {
  SIZE=2048
};

double A[SIZE][SIZE];

int main(void)
{
  for (int i = 0; i < SIZE; i++) {
    for (int j = 0; j < SIZE; j++) {
      // first time(1) with this version, then comment this
      // one, uncomment the other, time(1) again; since the
      // memory access pattern is different, performance is
      // different (on all machines I know anyway)...
      A[i][j] = 1.0;
      //A[j][i] = 1.0;
    }
  }
}