/* -*- coding: utf-8 -*-
 *
 * 3630.cc:  No.3630 Edge of triangle - yukicoder
 */

#include<cstdio>
#include<algorithm>

using namespace std;

/* main */

int main() {
  int a, b, c;
  scanf("%d%d%d", &a, &b, &c);
  
  if (a + b > c && b + c > a && c + a > b) puts("Yes");
  else puts("No");

  return 0;
}