Set Matrix Zeroes In Place in DSA C - Build from Scratch

Set Matrix Zeroes In Place

📖 Scenario: You are working with a grid of numbers representing a game board. Sometimes, certain cells become inactive and are marked with zero. To keep the board consistent, if any cell is zero, the entire row and column of that cell should become zero.

🎯 Goal: Modify the given matrix in place so that if any cell is zero, its entire row and column are set to zero. You will do this without using extra space for another matrix.

📋 What You'll Learn

Create a 2D integer array called matrix with the exact values given.

Create two integer variables rows and cols to store the matrix dimensions.

Implement the in-place algorithm to set matrix zeroes using the first row and first column as markers.

Print the matrix after modification in the specified format.

💡 Why This Matters

🌍 Real World

This technique is useful in image processing, game boards, and spreadsheet applications where certain cells becoming inactive affect entire rows and columns.

💼 Career

Understanding in-place matrix modification is important for software engineers working with memory-efficient algorithms and data manipulation.

1

Create the matrix

Create a 2D integer array called matrix with 3 rows and 4 columns containing these exact values: {{1, 1, 1, 0}, {1, 0, 1, 1}, {1, 1, 1, 1}}.

DSA C

# Create the matrix with the given values
// Your code here

Hint

Use a 2D array with 3 rows and 4 columns and fill it with the exact numbers given.

2

Set matrix dimensions

Create two integer variables called rows and cols and set them to 3 and 4 respectively to represent the matrix size.

DSA C

int matrix[3][4] = {
    {1, 1, 1, 0},
    {1, 0, 1, 1},
    {1, 1, 1, 1}
};

// Set rows and cols variables
// Your code here

Hint

Use two integer variables to store the number of rows and columns.

3

Implement in-place zero setting

Write code to set matrix zeroes in place using the first row and first column as markers. Use variables rows and cols for dimensions and modify matrix accordingly.

DSA C

int matrix[3][4] = {
    {1, 1, 1, 0},
    {1, 0, 1, 1},
    {1, 1, 1, 1}
};

int rows = 3;
int cols = 4;

// Implement the in-place zero setting algorithm
// Your code here

Hint

Use the first row and first column as markers to remember which rows and columns should be zeroed. Then update the matrix accordingly.

4

Print the modified matrix

Print the matrix after modification. Use nested loops with variables i and j to print each element separated by spaces, and print a newline after each row.

DSA C

Hint

Use nested loops to print each element separated by spaces. Print a newline after each row.