65_findMissingAndRepeatedValues'.py

'''You are given a 0-indexed 2D integer matrix grid of size n * n with values in the range [1, n2]. 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 to b.
Example 1:
Input: grid = [[1,3],[2,2]]
Output: [2,4]
Explanation: Number 2 is repeated and number 4 is missing so the answer is [2,4].'''
from typing import List
class Solution:
  def findMissingAndRepeatedValues(self, grid: List[List[int]]) -> List[int]:
    n=len(grid[0])
    repeat=-1
    hashSet=set()
    for i in range(len(grid)):
      for j in range(len(grid[i])):
        if grid[i][j] in hashSet:
          repeat=grid[i][j]
        else:
          hashSet.add(grid[i][j])
    for i in range(1,(n**2)+1):
      if i not in hashSet:
        return [repeat,i]