Help needed in Packing Rectangles (Binary Search)

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Help needed in Packing Rectangles (Binary Search)

Revision en1, by coder__12345, 2024-02-04 00:07:51

Accepted Code

#include<bits/stdc++.h>

using namespace std;

#define int long long


int a,b,n;

bool isfit(int mid){
	return (mid/a)*(mid/b)>=n;
}

signed main(){
	cin>>a>>b>>n;
	int l=0,r=1;
	while(isfit(r)==false){
		r*=2;
	}
	while(r-l>1){
		int mid=l+(r-l)/2;
		if(isfit(mid)){
			r=mid;
		}
		else{
			l=mid;
		}
	}
        if(isfit(l)) cout<<l<<endl;
        else cout<<r<<endl;
}

Not Accepted Code

#include<bits/stdc++.h>

using namespace std;

#define int long long


int a,b,n;

bool isfit(int mid){
	return (mid/a)*(mid/b)>=n;
}

signed main(){
	cin>>a>>b>>n;
	int l=0,r=1;
	while(isfit(r)==false){
		r*=2;
	}
	while(r-l>1){
		int mid=l+(r-l)/2;
		if(isfit(mid)){
			r=mid;
		}
		else{
			l=mid+1;
		}
	}
        cout<<l<<endl;
}

The only change in the two code is the value being assigned to l, when i normally implement binary search i use it like in the not accepted one but why in this problem its giving wrong answer?

History

Revisions

	Rev.	Lang.	By	When	Δ	Comment
	en2		coder__12345	2024-02-04 00:12:50	95
	en1		coder__12345	2024-02-04 00:07:51	1141	Initial revision (published)