tijie

#include<iostream>
#include<cmath>
using namespace std;
bool tr(int a,int b,int c){
    return a+b>c&&abs(a-b)<c;
}
int main(){
    int a,b,c;
    cin>>a>>b>>c;
    if(tr(a,b,c)&&tr(a,c,b)&&tr(b,c,a)) cout<<"YES";
    else cout<<"NO";
}