C Exercises: Calculate the determinant of a 3 x 3 matrix

C Array: Exercise-28 with Solution

Write a program in C to calculate the determinant of a 3 x 3 matrix.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>

int main() {
    int arr1[10][10], i, j, n;
    int det = 0;

    // Display the purpose of the program
    printf("\n\nCalculate the determinant of a 3 x 3 matrix :\n");
    printf("-------------------------------------------------\n");

    // Input elements into the matrix
    printf("Input elements in the matrix :\n");
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            printf("element - [%d],[%d] : ", i, j);
            scanf("%d", &arr1[i][j]);
        }
    }

    // Display the matrix
    printf("The matrix is :\n");
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            printf("% 4d", arr1[i][j]);
        }
        printf("\n");
    }

    // Calculate the determinant of the 3x3 matrix
    for (i = 0; i < 3; i++) {
        det = det + (arr1[0][i] * (arr1[1][(i + 1) % 3] * arr1[2][(i + 2) % 3] - arr1[1][(i + 2) % 3] * arr1[2][(i + 1) % 3]));
    }

    // Display the determinant of the matrix
    printf("\nThe Determinant of the matrix is: %d\n\n", det);

    return 0;
}

Sample Output:

Calculate the determinant of a 3 x 3 matrix :                                                                 
-------------------------------------------------                                                             
Input elements in the first matrix :                                                                          
element - [0],[0] : 1                                                                                         
element - [0],[1] : 0                                                                                         
element - [0],[2] : -1                                                                                        
element - [1],[0] : 0                                                                                         
element - [1],[1] : 0                                                                                         
element - [1],[2] : 1                                                                                         
element - [2],[0] : -1                                                                                        
element - [2],[1] : -1                                                                                        
element - [2],[2] : 0                                                                                         
The matrix is :                                                                                               
   1   0  -1                                                                                                  
   0   0   1                                                                                                  
  -1  -1   0                                                                                                  
                                                                                                              
The Determinant of the matrix is: 1 

Flowchart:

C Programming Code Editor:

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