Traffic jam

input/code.cpp: In function 'int main()':
input/code.cpp:17:14: error: 'sort' is not a member of 'std'; did you mean 'qsort'?
   17 |         std::sort(start, start + n);
      |              ^~~~
      |              qsort
input/code.cpp:18:14: error: 'sort' is not a member of 'std'; did you mean 'qsort'?
   18 |         std::sort(stop, stop + n);
      |              ^~~~
      |              qsort

#include <iostream>

using namespace std;

int main() {
    int n;
    cin >> n;
    int start [n];
    int stop [n];
    int arr2 [604810] = {0};

    for(int i = 0; i < n; i++) {
        int a,b;
        cin >> a >> b;
        start[i] = a;
        stop[i] = b;
        std::sort(start, start + n);
        std::sort(stop, stop + n);
    }

    for(int i = 0; i < 2*n; i++) {
        int j = start[i];
        arr2[j]++;
        j = stop[i];
        arr2[j]--;
    }


    int max = 0;
    for(int i = 0; i < 604800; i++) {
        if(arr2[i] > max) max = arr2[i];
    }
    cout << max << endl;


    /*int max = 0;
    int min = 604800;
    for(int i = 0; i < n; i++) {
        if(arr[i] > max) max = arr[i];
        if(arr[i] < min) min = arr[i];
    }

    int maxnumtotal = 0;
    for(int i = min; i < max; i++) {
        int maxNum = 0;
        for(int j = 0; j < n; j++) {
            if(arr[2*j] <= i && arr[2*j+1] >= i) {
                maxNum++;       
            }
        }
        if (maxNum > maxnumtotal) maxnumtotal = maxNum;
        if( maxNum == n) break;
    }
    cout << maxnumtotal << endl;*/
  
    
}