# 2965. Find Missing and Repeated Values """ you are given a 0-indexed 2d integer matrix 'grid' of size 'n n' with values in the range '[1, n^2]'. each integer appears exactly once except 'a' which appears twice and 'b' which is missing. the task is to find the repeating and missing numbers 'a' and 'b'. return a 0-indexed integer array 'ans' of size '2' where 'ans[0]' equals to 'a' and 'ans[1]' equals 'b'. """ class Solution(object): def findMissingAndRepeatedValues(self, grid): """ :type grid: List[List[int]] :rtype: List[int] """ repeated, missing, n = 0, 0, len(grid) cnt = [0] * (n * n + 1) for i in grid: for j in i: cnt[j] += 1 if cnt[j] == 2: repeated = j for i in range(1, n * n + 1): if cnt[i] == 0: missing = i break return [repeated, missing] if __name__ == "__main__": obj = Solution() print(obj.findMissingAndRepeatedValues(grid=[[1, 3], [2, 2]])) print(obj.findMissingAndRepeatedValues(grid=[[9, 1, 7], [8, 9, 2], [3, 4, 6]]))