Question link SPOJ-EKO
#include <bits/stdc++.h>
using namespace std;
long long int arr[1000009];
long long int checkit(long long int arr[], long long int start, long long int end, long long int m, long long int n)
{
long long int mid = start + ((end-start)/2);
long long int summ = 0;
if(start >= end) return -1;
for(long long int i = 0; i < n; i++)
{
if(arr[i] >= mid) summ += (arr[i]-mid);
}
if(summ > m)
{
return checkit(arr, mid, end, m, n);
}
else if(summ < m)
{
return checkit(arr, start, mid-1, m, n);
}
else
{
long long int d1 = checkit(arr, mid+1, end, m, n);
if(d1 == -1) return mid;
else return d1;
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
long long int n, m;
cin >> n >> m;
long long int end = -1;
for(long long int i = 0; i < n; i++)
{
cin >> arr[i];
end = max(end, arr[i]);
}
cout << checkit(arr, 0, end, m, n) << "\n";
return 0;
}
I don’t know what’s wrong with my code. To be honest, I am often confused about whether to take start = mid or start = mid+1 and end = mid or end = mid-1.