Mahmoud and a Triangle

#include <bits/stdc++.h>

using namespace std;

#define int long long

signed main()
{
    int n;
    cin >> n;
    vector<int> v(n);
    for(int i = 0; i < n; i++){
        cin >> v[i];
    }
    sort(v.begin() , v.end());
    bool ok = false;

    for(int i = 1; i < (n - 1); i++){
        int a = v[i - 1] , b = v[i] , c = v[i + 1];
        if((c < (a + b)) && (c > (b - a))){
            ok = true;
            break;
        }
    }
    cout << (ok ? "YES" : "NO") << endl;
}