Binary serch (page allocation )

#include <iostream>
using namespace std;
bool check(int arr[], int n, int m, int mid)
{
    int student = 1;
    int pagesum = 0;
    for (int i = 0; i < n; i++)
    {
        if (pagesum + arr[i] <= mid)
        {
            pagesum += arr[i];
        }
        else
        {
            student++;
            if (mid < arr[i] || m <student)
            {
                return false;
            }
            pagesum = arr[i];
        }
       
    }
    return true;
}
int possible_min(int arr[], int n, int m)
{
    int sum = 0;
    for (int i = 0; i < n; i++)
    {
        sum += arr[i];
    }
    int s = 0;
    int ans = -1;
    int e = sum;
    int mid = (s + e) / 2;
    while (s <= e)
    {
        if (check(arr, n, m, mid))
        {
            ans = mid;
            e=mid-1;
        }
        else
        {
            s=mid+1;
        }
        mid = (s + e) / 2;
    }
    return ans;
}
int main()
{
    int n;
    int m;
    cout << "ENTER THE SIZE OF ARRAY--->";
    cin >> n;
    int arr[100];
    for (int i = 0; i < n; i++)
    {
        cin >> arr[i];
    }
    for (int i = 0; i < n; i++)
    {
        cout << arr[i] << " ";
    }
    cout<<endl;
    cout << "ENTER THE STUDENT COUNT--->";
    cin >> m;
    cout<<endl;
    cout << "ANSWER--->" << possible_min(arr,n,m);

    return 0;