URL

Island Perimeter - LeetCode

Code

https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202404/island_perimeter/main.fsx

let islandPerimeter (grid: int[,]) : int =
    let mutable ret = 0
    let rows, cols = Array2D.length1 grid, Array2D.length2 grid

    for i in 0 .. (rows - 1) do
        for j in 0 .. (cols - 1) do
            if grid.[i, j] = 1 then
                ret <- ret + 4

                if i >= 1 && grid.[i - 1, j] = 1 then
                    ret <- ret - 2

                if j >= 1 && grid.[i, j - 1] = 1 then
                    ret <- ret - 2

    ret