#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: wengzihang
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/