Answer71.cpp

#include <bits/stdc++.h> 
bool ispossible( vector<int> arr,int n,int m,int mid){
    
    int studentcount=1;
    int pagesum=0;
    
    for(int i=0;i<n;i++)
    {
        if(pagesum + arr[i]<= mid)
        {
            pagesum = pagesum + arr[i];
        }
        else
        {
            studentcount++;
            if (studentcount> m || arr[i]>mid)
            {
                 return false;
                     
            }
            pagesum=arr[i];
        }
       
 
} 
    return true;
}


int allocateBooks(vector<int> arr, int n, int m) {

    int s=0;
    int sum=0;
    for(int i=0;i<n;i++){
        sum = sum + arr[i];  
    }
    int e=sum;
       int ans=-1;
    int mid=s+(e-s)/2;
    while(s<=e)
    {
        if(ispossible(arr,n,m,mid)){
            ans=mid;
            e=mid-1;
            
        }
        else
        {
            s= mid+1;
}
        mid=s+(e-s)/2;
    
    
    
} return ans;
    
}