There are 40 ways to make sums of three distinct positive integers total 25. (1+2+22 is such a sum, but 1+12+12 and 1+2+3+19 are not.)

How many different ways can three distinct positive integers sum to 1000?

int main() {
  int sum,a,b,c;
  for (a = 1; a < 999; a++)
    for (b = 1; b < 999; b++)
      for (c = 1; c < 999; c++)
 if (a != b && a != c && b != c)
   if (a + b + c == 1000) sum++;
  sum /= 6; //perm to comb - divide by 3!
  printf("%d\n", sum);
}

Posted by vectorboy on 2004-07-22 11:18:51