C Exercises: Display the lower triangular of a given matrix

C Array: Exercise-26 with Solution

Write a program in C to print or display the lower triangular of a given matrix.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>

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

    // Display the purpose of the program
    printf("\n\nDisplay the lower triangular of a given matrix :\n");
    printf("----------------------------------------------------\n");

    // Input the size of the square matrix
    printf("Input the size of the square matrix : ");
    scanf("%d", &n);

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

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

    // Display lower triangular matrix by setting upper triangular elements to zero
    printf("\nSetting zero in lower triangular matrix\n");
    for (i = 0; i < n; i++) {
        printf("\n");
        for (j = 0; j < n; j++) {
            if (i <= j) {
                printf("% 4d", arr1[i][j]); // Print the original elements if i <= j (lower triangular)
            } else {
                printf("% 4d", 0); // Print zero if i > j (upper triangular)
            }
        }
    }
    printf("\n\n");

    return 0;
}

Sample Output:

Display the lower triangular of a given matrix :                                                              
----------------------------------------------------                                                          
Input the size of the square matrix : 3                                                                       
Input elements in the first matrix :                                                                          
element - [0],[0] : 1                                                                                         
element - [0],[1] : 2                                                                                         
element - [0],[2] : 3                                                                                         
element - [1],[0] : 4                                                                                         
element - [1],[1] : 5                                                                                         
element - [1],[2] : 6                                                                                         
element - [2],[0] : 7                                                                                         
element - [2],[1] : 8                                                                                         
element - [2],[2] : 9                                                                                         
The matrix is :                                                                                               
   1   2   3                                                                                                  
   4   5   6                                                                                                  
   7   8   9 
Setting zero in lower triangular matrix                                                                       
                                                                                                              
   1   2   3                                                                                                  
   0   5   6                                                                                                  
   0   0   9                                     

Flowchart:

C Programming Code Editor:

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