#include<bits/stdc++.h>
using namespace std;
int main(){
int a,b,c;
cin>>a>>b>>c;
if(a+b>c&&a+c>b&&b+c>a) cout<<"Yes";
else cout<<"No";
}
/**************************************************************
Problem: 1045
User: jiangyuanfeng
Language: C++
Result: Accepted
Time:10 ms
Memory:2072 kb
****************************************************************/