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832. Flipping an Image

Difficulty Topics

Description

Given an n x n binary matrix image, flip the image horizontally, then invert it, and return the resulting image.

To flip an image horizontally means that each row of the image is reversed.

  • For example, flipping [1,1,0] horizontally results in [0,1,1].

To invert an image means that each 0 is replaced by 1, and each 1 is replaced by 0.

  • For example, inverting [0,1,1] results in [1,0,0].

 

Example 1:

Input: image = [[1,1,0],[1,0,1],[0,0,0]]
Output: [[1,0,0],[0,1,0],[1,1,1]]
Explanation: First reverse each row: [[0,1,1],[1,0,1],[0,0,0]].
Then, invert the image: [[1,0,0],[0,1,0],[1,1,1]]

Example 2:

Input: image = [[1,1,0,0],[1,0,0,1],[0,1,1,1],[1,0,1,0]]
Output: [[1,1,0,0],[0,1,1,0],[0,0,0,1],[1,0,1,0]]
Explanation: First reverse each row: [[0,0,1,1],[1,0,0,1],[1,1,1,0],[0,1,0,1]].
Then invert the image: [[1,1,0,0],[0,1,1,0],[0,0,0,1],[1,0,1,0]]

 

Constraints:

  • n == image.length
  • n == image[i].length
  • 1 <= n <= 20
  • images[i][j] is either 0 or 1.

Solution

flipping-an-image.py
class Solution:
    def flipAndInvertImage(self, A: List[List[int]]) -> List[List[int]]:
        n = len(A)
        res = []

        for i in range(n):
            tmp = []
            for j in reversed(A[i]):
                tmp.append(j ^ 1)

            res.append(tmp)

        return res