#include <bits/stdc++.h>
using namespace std;
int main(){
   int a,s,d;
   cin>>a>>s>>d;
    if(a+s>d&&a+d>s&&s+d>a){
    	cout<<"Yes";
    }else{
    	cout<<"No";
    }
}
    	
/**************************************************************
	Problem: 1045
	User: huangluowei
	Language: C
	Result: Compile Error
****************************************************************/