题解 100% AC

#include<bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c;cin>>a>>b>>c; 
    bool d=1;
    if(a+b<=c||a+c<=b||b+c<=a)d=0;
    if(d)cout<<"yes";
    else cout<<"no";
	return 0;
}