C Exercises: Display the upper triangular of a given matrix

C Array: Exercise-27 with Solution

Write a program in C to print or display an upper triangular matrix.

The task is to write a C program that prints the upper triangular matrix of a given square matrix. The program prompts the user to input the size of the matrix and its elements, displays the original matrix, then modifies the matrix to show only its upper triangular part (where elements below the main diagonal are set to zero) and prints this modified matrix as output.

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 upper 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 upper triangular matrix by setting lower triangular elements to zero
    printf("\nSetting zero in upper 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 (upper triangular)
            } else {
                printf("% 4d", 0); // Print zero if i < j (lower triangular)
            }
        }
    }
    printf("\n\n");

    return 0;
}

Sample Output:

Display the upper 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 upper triangular matrix                                                                       
                                                                                                              
   1   0   0                                                                                                  
   4   5   0                                                                                                  
   7   8   9   

Flowchart:

C Programming Code Editor:

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