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Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.



Given a n*n grid, output the index of the island with the longest coast, followed by the amount of water it holds. (Island indexes are 1-indexed)

An island is made of one or more # characters, we'll call that an island block. While water is represented by ~.

We start from the first row and go through the columns left to right till the last row, when encountering a block that you haven't visited yet, that means it is the start of a new island, therefore that is now the ith island, it may connect other blocks in four directions: up, down, left and right, meaning only horizontal and vertical directions. these blocks may also connect other blocks, this goes on until there are no other connected blocks, and once there is no connection anymore, we look for a new island using the same process.

If multiple islands have the same amount of water, output the one with a smaller index.


With n = 5:


We see that the 2nd island is the one with the longest coast, because the first block is surrounded by 3 water blocks and so is the second block. once summed up we get 6, which is greater than the first island having only 4. so in this case, we output 2 6 (island 2, 6 water blocks).
Line 1: An integer n representing the size of the grid
Next n lines: A row of the grid of length n
The index of the island with most water surrounding it followed by the amount separated by a space.
3 ≤ n ≤ 50
1 3

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