#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: chenjiahui
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/