Problem: Flipping an Image

Medium

30 min

Explore how to flip an image horizontally and invert its pixels using bitwise techniques in Python. Understand the approach to manipulate square matrix images of 0s and 1s, and practice implementing efficient solutions to this common coding interview problem.

Statement

Given that an image is represented by an $(n \times n)$ matrix containing $0$ s and $1$ s, flip and invert the image, and return the resultant image.

Horizontally flipping an image means that the mirror image of the matrix should be returned. Flipping $[1, 0, 0]$ horizontally results in $[0, 0, 1]$ .

Inverting an image means that every $0$ is replaced by $1$ , and every $1$ is replaced by $0$ . Inverting $[0, 1, 1]$ results in $[1, 0, 0]$ .

Constraints:

Image should be a square matrix.
$1 \leq n \leq 20$
images[i][j] is either $0$ or $1$ .

Flipping an Image

Consider the following $(3 \times 3)$ matrix as input. What is the output once it has been flipped and inverted?

\begin{bmatrix} 1 & 1 & 0 \\ 0 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 1 & 0 \\ 0 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 0 & 0 \\ 0 & 1 & 1 \\ 0 & 0 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 1 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

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Problem: Flipping an Image

Medium

30 min

Statement

Given that an image is represented by an $(n \times n)$ matrix containing $0$ s and $1$ s, flip and invert the image, and return the resultant image.

Horizontally flipping an image means that the mirror image of the matrix should be returned. Flipping $[1, 0, 0]$ horizontally results in $[0, 0, 1]$ .

Inverting an image means that every $0$ is replaced by $1$ , and every $1$ is replaced by $0$ . Inverting $[0, 1, 1]$ results in $[1, 0, 0]$ .

Constraints:

Image should be a square matrix.
$1 \leq n \leq 20$
images[i][j] is either $0$ or $1$ .

Flipping an Image

Consider the following $(3 \times 3)$ matrix as input. What is the output once it has been flipped and inverted?

\begin{bmatrix} 1 & 1 & 0 \\ 0 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 1 & 0 \\ 0 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 0 & 0 \\ 0 & 1 & 1 \\ 0 & 0 & 1 \end{bmatrix}

\begin{bmatrix} 1 & 1 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 1 \end{bmatrix}

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Problem: Flipping an Image

Statement

Examples

Understand the problem

Figure it out!

Try it yourself

Problem: Flipping an Image

Statement

Examples

Understand the problem

Figure it out!

Try it yourself