#include <bits/stdc++.h>
int main() {
  int a, b, c;
  do scanf("%d%d%d", &a, &b, &c);
  while (a <= 500 && a >= 1 && b <= 500 && b >= 1 && c >= 1 && c <= 1000);
  if (a + b >= c)
    printf("yes");
  else
    printf("no");
  return 0;
}
