Example: Interchange Two Rows in a Matrix in C

// Interchange Two Rows in a Matrix
#include <stdio.h>

#define ROWS 3
#define COLS 3

// Function to print the matrix
void printMatrix(int matrix[ROWS][COLS]) {
    for (int i = 0; i < ROWS; i++) {
        for (int j = 0; j < COLS; j++) {
            printf("%d ", matrix[i][j]);
        }
        printf("\n");
    }
}

int main() {
    // Step 1: Initialize the matrix
    int matrix[ROWS][COLS] = {
        {1, 2, 3},
        {4, 5, 6},
        {7, 8, 9}
    };

    int row1, row2; // Rows to interchange
    int temp;       // Temporary variable for swapping

    printf("Original Matrix:\n");
    printMatrix(matrix);

    // Step 2: Get user input for rows to swap
    printf("Enter the first row to interchange (0 to %d): ", ROWS - 1);
    scanf("%d", &row1);
    printf("Enter the second row to interchange (0 to %d): ", ROWS - 1);
    scanf("%d", &row2);

    // Validate input rows
    if (row1 < 0 || row1 >= ROWS || row2 < 0 || row2 >= ROWS) {
        printf("Invalid row numbers. Please enter values between 0 and %d.\n", ROWS - 1);
        return 1;
    }

    // Step 3: Interchange the elements of the specified rows
    for (int j = 0; j < COLS; j++) {
        temp = matrix[row1][j];
        matrix[row1][j] = matrix[row2][j];
        matrix[row2][j] = temp;
    }

    printf("\nMatrix after interchanging Row %d and Row %d:\n", row1, row2);
    printMatrix(matrix);

    return 0;
}