릿코드 463. Island Perimeter 코틀린

크기작으니까 그냥 o(n^2)쓰면서 상하좌우중 0인거의 갯수만큼 다 더하면될듯
함수로 뺴는게 더깔끔할거같긴한데 귀찮다

정답

class Solution {
    fun islandPerimeter(grid: Array<IntArray>): Int {
        var res=0
        for (i in grid.indices) {
            for (j in grid[0].indices) {
                if (grid[i][j] == 1) {
                    if (i+1>=grid.size){
                        res+=1
                    }else{
                        if(grid[i+1][j]==0){
                            res+=1
                        }
                    }
                    if (i-1<0){
                        res+=1
                    }else{
                        if(grid[i-1][j]==0){
                            res+=1
                        }
                    }

                    if (j+1>=grid[0].size){
                        res+=1
                    }else{
                        if(grid[i][j+1]==0){
                            res+=1
                        }
                    }
                    if (j-1<0){
                        res+=1
                    }else{
                        if(grid[i][j-1]==0){
                            res+=1
                        }
                    }
                }


            }
        }
        return res

    }
}