I am getting 1 extra in my output

#1 
// test case 2 4 10 20 30 40
#include<iostream>
#include<algorithm>
using namespace std;
bool isvalid(int k,int n,int a[],int mid)
{   int time=0;
    int painter_used=1;
    for (int i = 0; i < n; i++)
    {    time=time+a[i];
        if (time>=mid)
        {   time=a[i];
            painter_used++;
        }
       
        
        
        
    }
    return painter_used<=k;
    
}
int main(){
    int k;int n;
    cin>>k>>n;
    int a[n];
    int sum=0;
    for (int i = 0; i < n; i++)
    {
        cin>>a[i];
        sum+=a[i];
    }
    int start=*max_element(a,a+n);
    int end=sum;
    int ans=0;
    while (start<=end)
    {
        int mid=(start+end)/2;
        if (isvalid(k,n,a,mid))
        {   ans=mid;
            end=mid-1;
        }
        else
        {
            start=mid+1;
        }
        
        
    }
    cout<<ans;
    return 0;
}
#2

Here’s your debugged code

#3

why you updated the ans =start???

#4

This is because we want maximum painter used and wherever our start will point, it will be our maximum painter.

#5

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