Skip to content
Related Articles

Related Articles

Java Program to Print Boundary Elements of the Matrix
  • Last Updated : 04 Jan, 2021

Given a matrix of size Row x Col Print the boundary elements of the matrix. Boundary elements are those elements which are not surrounded by elements on all four directions, i.e. elements in the first row, first column, last row and last column.

Example:

Input :
         1 2 3
         4 5 6
         7 8 9
Output:  
        1 2 3
        4   6
        7 8 9

Approach:

  1. Take the matrix as input from the user of N × M dimension.
  2. Print the border elements of the matrix using for loop.

Below is the implementation of the problem statement:

Java

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java Program to Print Boundary
// Elements of the Matrix
  
import java.util.*;
  
public class GFG {
  
    public void Boundary_Elements(int mat[][])
    {
        // Printing Input Matrix;
        System.out.println("Input Matrix is : ");
  
        for (int i = 0; i < mat.length; i++) {
            for (int j = 0; j < mat[i].length; j++) {
  
                System.out.print(mat[i][j]);
            }
  
            System.out.println();
        }
  
        // Printing Boundary Values of Matrix
        System.out.println("Resultant Matrix is :");
  
        for (int i = 0; i < mat.length; i++) {
            for (int j = 0; j < mat[i].length; j++) {
  
                if (i == 0 || j == 0 || i == mat.length - 1
                    || j == mat[i].length - 1) {
                    System.out.print(mat[i][j]);
                }
                else {
                    // Printing Space if element
                    // is not at Boundary
                    System.out.print(" ");
                }
            }
  
            System.out.println();
        }
    }
    public static void main(String[] args)
    {
        // Input Matrix
        int mat[][] = new int[][] { { 1, 2, 3 },
                                    { 4, 5, 6 },
                                    { 7, 8, 9 } };
  
        GFG B_Values = new GFG();
  
        B_Values.Boundary_Elements(mat);
    }
}

chevron_right


Output



Input Matrix is : 
123
456
789
Resultant Matrix is :
123
4 6
789

Time Complexity: O(N × M), where n and m are the dimensions of the matrix.

Space Complexity: O(N × M).

Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up
Recommended Articles
Page :