릿코드 1582. Special Positions in a Binary Matrix 코틀린

가로로 쫙더한거랑 세로로 쫙더한거 만들어두고,전체for돌려서 둘다 1이고 자기자신도 1인거 찾으면+1
가로세로있는건 헷갈리니까 row,column으로 ij대신하자

정답

class Solution {
    fun numSpecial(mat: Array<IntArray>): Int {

        var res=0
        val rowList= MutableList(mat.size){0}
        val columnList=MutableList(mat[0].size){0}

        for (row in 0 until mat.size){
            for (column in 0 until  mat[0].size){
                if (mat[row][column]==1) {
                    rowList[row]++
                    columnList[column]++
                }
            }
        }

        for (row in 0 until mat.size){
            for (column in 0 until  mat[0].size){
                if (mat[row][column]==1 && rowList[row]==1 && columnList[column]==1){
                    res+=1
                }
            }
        }
        println(res)
    return res
    }
}