Flipping an Image · Interview Problem

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Leetcode

Medium

Arrays

Matrices

Bit Manipulation

Flipping an Image

Flip a binary matrix horizontally and then invert every bit.

Acceptance 100%

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Problem Statement

Problem

You are given an $n \times n$ binary matrix image where each element is either 0 or 1.

Perform two operations in order:

Flip horizontally each row, so the row is reversed from left to right.
Invert the matrix, changing every 0 to 1 and every 1 to 0.

Return the transformed matrix.

Notes

Flipping horizontally means reversing each row independently.
Inverting means replacing each bit with its opposite value.

Input Format

An integer matrix image of size $n \times n$
image[i][j] is either 0 or 1

Output Format

Return the matrix after horizontally flipping each row and then inverting every value.

Constraints

$1 \le n \le 20$
image is a square matrix
Each entry is either 0 or 1

Examples

Sample cases returned by the problem API.

Example 1

Input

image = [[1,1,0],[1,0,1],[0,0,0]]

Output

[[1,0,0],[0,1,0],[1,1,1]]

Explanation

Reverse each row first: [[0,1,1],[1,0,1],[0,0,0]]. Then invert every bit: [[1,0,0],[0,1,0],[1,1,1]].

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