agreed

How does integration involve over here? Can u plz explain? I m nt getting it!

I think the point of the challenge is to solve the problem using a Queue, rather than just trying to solve it using any possible solution.

Thanks for the feedback. However, the level of difficulty sometimes varies as perceived by differnet users, to some extent!

Can't be that easy as you failed to solve it using queue, as the problem and category intended!

https://www.hackerrank.com/challenges/truck-tour/forum/comments/128778

I totally agree. But it still got me because it was under the Queues topic and I thought I needed to use a queue. But I ended up not needing to use any advanced container AT ALL.

It's about queues insofar as the input stream is a queue. So, it's a degenerate case.

Don't need integration, minima, or any such. Don't even need a queue or container, really.

Either the problem is solvable or it's not -- but the problem statement doesn't leave room for unsolvable.

Thus assuming it's solvable, and you're looking for the lowest index from which it works, vinay_star_lord's solution (which I came up with on my own) works without a container, i.e., constant space.

Simple Array operation :

public class Solution {

    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        int n=in.nextInt();
        int litr[]=new int [n];
        int km[]=new int [n];
        long cap_value[]=new long[n];
        for(int i=0;i<n;i++){
            litr[i]=in.nextInt();
            km[i]=in.nextInt();
            cap_value[i]=(litr[i]-km[i]);
        }
       int pos=0;
        for(int i=0;i<n;i++){
             long ptl=0;int check=0;
            for(int j=0;j<n;j++){
            ptl+=cap_value[(j+pos)%n];
            if(ptl<0){++pos;check=-9;break;}
            }
            if(check==0){System.out.print(pos);break;}
        }
    }
}