#include <stdio.h>

int
main(int argv, char **argc)
{
  double i;
  double sum = 0;                                                // Line 7

  for(i=1; i<50000000;)                                          // Line 9
    {
      sum = sum + 4.0 / i;   i += 2;                             // Line 11
      sum = sum - 4.0 / i;   i += 2;                             // Line 12
    }

  printf("After %d iterations sum = %.8f\n", (int)(i-1)/2, sum); // Line 15

  return 0;
}