#include <stdio.h>
#include <stdint.h>

// Compile with -O0

int main(int argc, char *argv[]) {
  int i;
  uint64_t n;
  float x = 1.3;
  double z;

  // This should be 1.3, right?
  printf("%f\n", x);

  // Nope!
  printf("%.15f\n", x);

  // Now let's compute 1.3*10
  for (i = 1; i <= 9; ++i)
    x += 1.3;

  // We expect to get 13, but we don't
  if (x == 13.0) {
    printf("x == 13.0\n");
  } else {
    printf("x != 13.0\n");
  }
  printf("%.6f\n", x);
  printf("%.15f\n", x);

  // And we get a different answer if we multiply instead of add
  x = 1.3;
  x *= 10.0f;
  printf("%.15f\n", x);

  // Let's make a big number that we can represent
  // precisely with floating point
  n = (uint64_t)1<<63;
  x = (float)n;
  printf("%f\n", x);
  printf("%.15f\n", x);

  // This is also precise
  printf("%.15f\n", 0.25);

  // Small number plus a big number: the small number goes away!
  x += 0.25;
  printf("%f\n", x);
  printf("%.15f\n", x);

  // doubles are more precise, but still imprecise
  x = 0.1;
  z = 0.1;
  printf("%.30f\n", x);
  printf("%.30f\n", z);

  return 0;
}