#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: lijinkai
Language: C++
Result: Accepted
Time:6 ms
Memory:2072 kb
****************************************************************/