#include <bits/stdc++.h>
using namespace std;
const long double EPS = 1e-9;
const long long mod = 1e9 + 7;
const long long INF = 1e9;
const long long MAX_N = 100000;
int main(void) {
  long long a, b, c;
  cin >> a >> b >> c;
  if (a * 2 + b >= c)
    cout << "Yes";
  else
    cout << "No";
  return 0;
}
