Create Car-Fleet-II.java

[sp995]

Pull Request Template

Description

This PR adds a solution for the problem "419. Battleships in a Board" from LeetCode.
The goal is to count the number of battleships present on a given 2D board without modifying the board or using extra space.

Approach:

We iterate through each cell in the board. For a cell containing 'X', we check if it is the top-left-most part of a new battleship by ensuring there's no 'X' directly above or to the left. If these conditions hold, we increment the battleship count.

Dependencies:

No external dependencies are required for this change.

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Put check marks:

Have you made changes in README file?

• [x] Added problem & solution under correct topic.
• [x] Specified Space & Time complexity.
• [x] Specified difficulty level, tag & Note(if any).

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How Has This Been Tested?

The solution has been tested using a sample input and produces the correct number of battleships.

• [x] Test A: Sample board with two battleships
• [ ] Test B

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Make sure all below guidelines are followed else PR will get Rejected:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code so that it is easy to understand
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] Any dependent changes have been merged and published in downstream modules