LeetCode in Kotlin

2661. First Completely Painted Row or Column

Medium

You are given a 0-indexed integer array arr, and an m x n integer matrix mat. arr and mat both contain all the integers in the range [1, m * n].

Go through each index i in arr starting from index 0 and paint the cell in mat containing the integer arr[i].

Return the smallest index i at which either a row or a column will be completely painted in mat.

Example 1:

image explanation for example 1

Input: arr = [1,3,4,2], mat = [[1,4],[2,3]]

Output: 2

Explanation: The moves are shown in order, and both the first row and second column of the matrix become fully painted at arr[2].

Example 2:

image explanation for example 2

Input: arr = [2,8,7,4,1,3,5,6,9], mat = [[3,2,5],[1,4,6],[8,7,9]]

Output: 3

Explanation: The second column becomes fully painted at arr[3].

Constraints:

Solution

class Solution {
    fun firstCompleteIndex(arr: IntArray, mat: Array<IntArray>): Int {
        val map: HashMap<Int, Int> = HashMap()
        var ans = mat.size * mat[0].size
        for (i in arr.indices) {
            map.put(arr[i], i)
        }
        for (i in mat.indices) {
            var maxV = 0
            for (j in mat[0].indices) {
                maxV = maxV.coerceAtLeast(map[mat[i][j]]!!)
            }
            ans = ans.coerceAtMost(maxV)
        }
        for (i in mat[0].indices) {
            var maxV = 0
            for (j in mat.indices) {
                maxV = maxV.coerceAtLeast(map[mat[j][i]]!!)
            }
            ans = ans.coerceAtMost(maxV)
        }
        return ans
    }
}