#include <bits/stdc++.h>
using namespace std;
int main(){int a,b,c;  
cin>>a>>b>>c;
if(a+b>c&&a+c>b&&c+b>a)cout<<"Yes";
else cout<<"No";
	return 0;
	}

/**************************************************************
	Problem: 1045
	User: lyy002
	Language: C++
	Result: Accepted
	Time:15 ms
	Memory:2072 kb
****************************************************************/