Program to print Lower triangular and Upper triangular matrix of an array

Prerequisite - Multidimensional Arrays in C / C++
Given a two dimensional array, Write a program to print lower triangular matrix and upper triangular matrix. 

• Lower triangular matrix is a matrix which contains elements below principal diagonal including principal diagonal elements and rest of the elements are 0.
• Upper triangular matrix is a matrix which contains elements above principal diagonal including principal diagonal elements and rest of the elements are 0.

LOWER TRIANGULAR : 

UPPER TRIANGULAR : 

Examples : 

Input : matrix[3][3] = {1 2 3
 4 5 6
 7 8 9}
Output :
Lower : 1 0 0 Upper : 1 2 3
 4 5 0 0 5 6
 7 8 9 0 0 9

Input : matrix[3][3] = {7 8 9
 3 2 1
 6 5 4}
Output :
Lower : 7 0 0 Upper : 7 8 9
 3 2 0 0 2 1
 6 5 4 0 0 4

Steps: 

1. For lower triangular matrix, we check the index position i and j i.e. row and column respectively. If column position is greater than row position we simply make that position 0.
2. For upper triangular matrix, we check the index position i and j i.e. row and column respectively. If column position is smaller than row position we simply make that position 0.

Lower triangular matrix: 
1 0 0 
4 5 0 
7 8 9 
Upper triangular matrix: 
1 2 3 
0 5 6 
0 0 9 

Time Complexity: O(row x col)
Auxiliary Space: O(1), since no extra space has been taken.