#include <bits/stdc++.h>
int main() {
  int a, b, c;
  a, b, c >= 1 && a, b, c <= 100;
  scanf("%d", &a);
  scanf("%d", &b);
  scanf("%d", &c);
  if (a + b >= c && a + c >= b && c + b >= a) {
    printf("Yes");
  } else {
    printf("No");
  }
  return 0;
}
