GFG_MinCostOfRopes.cpp

/*
https://practice.geeksforgeeks.org/problems/minimum-cost-of-ropes-1587115620/1
Minimum Cost of ropes 
*/

// { Driver Code Starts
#include <bits/stdc++.h>
using namespace std;


 // } Driver Code Ends
class Solution
{
    public:
    //Function to return the minimum cost of connecting the ropes.
    long long minCost(long long arr[], long long n) {
        
        priority_queue<long long, vector<long long>, greater<long long>> minh(arr, arr+n);
        
        long long cost = 0;
        
        while(minh.size()>1)
        {
            long long n1 = minh.top(); minh.pop();
            long long n2 = minh.top(); minh.pop();
            cost += n1+n2;
            minh.push(n1+n2);
            
        }
        
        return cost;
    }
};


// { Driver Code Starts.

int main() {
    long long t;
    cin >> t;
    while (t--) {
        long long n;
        cin >> n;
        long long i, a[n];
        for (i = 0; i < n; i++) {
            cin >> a[i];
        }
        Solution ob;
        cout << ob.minCost(a, n) << endl;
    }
    return 0;
}
  // } Driver Code Ends