menu
What is the correct approach to solve aggressive cows problem?
What is the correct approach to solve aggressive cows problem?
Coding Interview Problem

Are you looking for an optimal solution to resolve aggressive cows' problems

Aggressive cow problem is one advanced problem which is often asked about in interviews and exams. The problem perfectly judges how good an understanding you have of the basic coding concepts.

The problem is an advanced version of a binary search problem. Therefore, to resolve the problem, all you have to do is to implement a binary search and find out the stalls in which you can place aggressive cows in the barn.

However, if you are new to this problem and you are not aware of what needs to be done, let’s understand the problem statement first. 

 

Problem Statement

There is a farmer named John. He has built a barn which has N number of stalls and all of them are aligned in a single line denoted by X.

Now, he has to accommodate his C cows in the barn he has created. However, the problem is that his cows have not liked the barn he has built and are now aggressive. 

You will have to write a code to determine the largest minimum distance at which John can accommodate his cows in a way that they do not fight each other. 

Here, the following input and output are provided to you.

Input: 

Line 1: You will be given two space integers, i.e, N and C.

Line 2: N+1: Line i+1. This will depict the stall locations, also denoted by xi.

T: it determines the total number of test cases to be followed.

Output:

The output should return an integer which will be the largest minimum distance.

To understand the aggressive cow's problem in a better way, consider the following example:

Given Array: { 1, 2, 4, 8, 9}

K= 3

Output= 3.

Here, John can place his first cow in stall 1, the second one in stall 4 and the last one in stall 8.

 

How To Resolve Aggressive Cows Problem?

To resolve the aggressive cows' problem, you can use binary search. The steps involved in the process are as follows:

  • First, know that the value of xi will range from 0 to 10^9. This is why the required distance will lie between this range. This means that the minimum distance between any two stalls can be as small as 0 or as large as 10^9.

  • Therefore, you will have to find the optimal value between the upper and lower values. Let’s consider that the minimum distance between two cows is K. So, we will have to check if you can place the cows in a specific stall or not. In case you are not able to place every cow in the stalls till you reach the last stall, it simply means that your solution is not optimal.

  • Another thing that you will have to consider is that if you can place K cows in all the stalls, for any value less than k, the same solution is feasible.

  • But if you are not able to find an optimal solution for K, the solution will not work for any value above k.

  • Moreover, the solution can also be treated as a monotonic function where you will have to change the value where your output switches from true to false. In the end, you need to find the value where the transition has taken place.

  • You can get this value with the help of a binary search within the specified range.

However, if you are not aware of how binary search works, let’s take a look at it as well.

 

Understanding Binary Search

Binary search is performed only on a sorted array. In this method, the given array is divided into two halves and then searching is done. A binary search is performed to leverage the fact that the given array is sorted and reduce the time complexity for it. 

The steps involved in the binary search are:

  • To begin with, consider that the middle element of the array is the primary or search key of the given array.

  • In case your search key is equal to the element, you will have to return the address of the search key.

  • Moreover, if the element is smaller than your search key, you will have to focus on the first half of the array.

  • And if it is larger than the required element, you will have to focus on the second half.

  • Similarly, you will have to repeat this process until you find the required element or the given interval is empty.

In the same way, binary search is used to solve the aggressive cows' problem. 

Now that we are discussing some advanced problems that one can face in an interview, how can we not talk about the House Robber 2 problem? Let’s take a look at the horse robber 2 problems as well. 

 

House Robber 2 Problem

You are a professional robber who has robbed all the houses on one street. Now, you have found a new street to rob houses.

Here, all the houses are present in a circle. This means that one house will be the neighbour of its previous and next house. Moreover, the houses will share a similar security system.

You will be given an array of integer values which will indicate the amount that each house has. You need to write a code to determine the maximum amount of money you can rob from that street without being noticed by the police.

 

Conclusion

Interview processes have become a bit more advanced and stricter than earlier. This is why you need to prepare and learn to resolve advanced problems to clear an interview with ease.

Aggressive cows problem is one such advanced problem that you may encounter in your competitive exams or interviews and the only way to resolve it is through binary search. 

 

We have explained to you the complete solution along with the binary search algorithm so that you do not have to go anywhere else looking for solutions.