Minimum Platforms

//{ Driver Code Starts
// Program to find minimum number of platforms
// required on a railway station
#include <bits/stdc++.h>
using namespace std;


// } Driver Code Ends
class Solution{
    public:
    //Function to find the minimum number of platforms required at the
    //railway station such that no train waits.
    int findPlatform(int arr[], int dep[], int n)
    {
        // Your code here
        vector<pair<int,int>> v(n);
        for(int i=0;i<n;i++)
        {
            v[i]={arr[i],dep[i]};
        }
        sort(v.begin(),v.end());

        priority_queue<int,vector<int>,greater<int>> q;
        q.push(v[0].second);
        int c=1;
        for(int i=1;i<n;i++)
        {
            if(q.top()>=v[i].first)
            {

                c++;
            }
            else
            {
                q.pop();
            }
            q.push(v[i].second);
        }
        return c;
    }
};


//{ Driver Code Starts.
// Driver code
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int n;
        cin>>n;
        int arr[n];
        int dep[n];
        for(int i=0;i<n;i++)
            cin>>arr[i];
        for(int j=0;j<n;j++){
            cin>>dep[j];
        }
        Solution ob;
        cout <<ob.findPlatform(arr, dep, n)<<endl;
    }
   return 0;
}
// } Driver Code Ends
https://practice.geeksforgeeks.org/problems/minimum-platforms-1587115620/