#include<iostream> using namespace std; int main() { int a,b,c; cin>>a>>b>>c; if(((a+b>c)&&((a-b<c)||(b-a<c)))&&((a+c>b)&&((a-c<b)||(c-a<b)))&&((b+c>a)&&((b-c<a)||(c-b<a)))) cout<<"yes"; else cout<<"no"; }