#include<iostream>
using namespace std;

int main(){

	int a,b,c;
	cin >> a >> b >> c;

	if((a+b)<=c) cout << "No" << endl;
	else if((a+c)<=b) cout << "No" << endl;
	else if((b+c)<=a) cout << "No" << endl;
	else cout << "Yes" << endl;

    return 0;
}