Remove first X rows and columns from a matrix
Given an integer X and a square matrix mat[][], the task is to remove the first X rows and columns from the given matrix and print the updated matrix.
Examples:
Input: mat[][] = {
{1, 2, 3, 4},
{5, 6, 7, 8},
{8, 9, 4, 2},
{4, 8, 9, 2} },
X = 2
Output:
4 2
9 2Input: mat[][] = {
{1, 2, 3},
{4, 5, 6},
{7, 8, 9} },
X = 1
Output:
5 6
8 9
Approach: Print the elements of the matrix arr[i][j] for all i, j ? [X, N – 1] where N is the order of the given square matrix.
Below is the implementation of the above approach:
C++
// C++ implementation of the approach #include <iostream> using namespace std; const int MAX = 50; // Function to print the matrix after // ignoring first x rows and columns void remove_row_col( int arr[][MAX], int n, int x) { // Ignore first x rows and columns for ( int i = x; i < n; i++) { for ( int j = x; j < n; j++) { cout << arr[i][j] << " " ; } cout << endl; } } // Driver Code int main() { // Order of the square matrix int n = 3; int arr[][MAX] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } }; int x = 1; remove_row_col(arr, n, x); } |
Java
// Java implementation of the approach import java.io.*; class GFG { static int MAX = 50 ; // Function to print the matrix after // ignoring first x rows and columns static void remove_row_col( int arr[][], int n, int x) { // Ignore first x rows and columns for ( int i = x; i < n; i++) { for ( int j = x; j < n; j++) { System.out.print( arr[i][j] + " " ); } System.out.println(); } } // Driver Code public static void main (String[] args) { // Order of the square matrix int n = 3 ; int arr[][] = { { 1 , 2 , 3 }, { 4 , 5 , 6 }, { 7 , 8 , 9 } }; int x = 1 ; remove_row_col(arr, n, x); } } // This code is contributed by // shk |
Python3
# Python3 implementation of the approach # Function to print the matrix after # ignoring first x rows and columns def remove_row_col(arr, n, x): # Ignore first x rows and columns for i in range (x, n): for j in range (x, n): print (arr[i][j], end = " " ) print () # Driver Code if __name__ = = "__main__" : # Order of the square matrix n = 3 MAX = 50 arr = [[ 1 , 2 , 3 ], [ 4 , 5 , 6 ], [ 7 , 8 , 9 ]] x = 1 remove_row_col(arr, n, x) # This code is contributed by Rituraj Jain |
C#
// C# implementation of the approach using System; class GFG { // Function to print the matrix after // ignoring first x rows and columns static void remove_row_col( int [,]arr, int n, int x) { // Ignore first x rows and columns for ( int i = x; i < n; i++) { for ( int j = x; j < n; j++) { Console.Write(arr[i, j] + " " ); } Console.WriteLine(); } } // Driver Code public static void Main() { // Order of the square matrix int n = 3; int [,]arr = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } }; int x = 1; remove_row_col(arr, n, x); } } // This code is contributed by Ryuga |
PHP
<?php // PHP implementation of the approach $MAX = 50; // Function to print the matrix after // ignoring first x rows and columns function remove_row_col( $arr , $n , $x ) { // Ignore first x rows and columns for ( $i = $x ; $i < $n ; $i ++) { for ( $j = $x ; $j < $n ; $j ++) { echo $arr [ $i ][ $j ] . " " ; } echo "\n" ; } } // Driver Code // Order of the square matrix $n = 3; $arr = array ( array ( 1, 2, 3 ), array ( 4, 5, 6 ), array ( 7, 8, 9 )); $x = 1; remove_row_col( $arr , $n , $x ); // This code is contributed by ihritik ?> |
Javascript
<script> // Javascript implementation of the approach let MAX = 50; // Function to print the matrix after // ignoring first x rows and columns function remove_row_col(arr,n,x) { // Ignore first x rows and columns for (let i = x; i < n; i++) { for (let j = x; j < n; j++) { document.write( arr[i][j] + " " ); } document.write( "<br>" ); } } // Driver Code // Order of the square matrix let n = 3; let arr = [[ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ]]; let x = 1; remove_row_col(arr, n, x); // This code is contributed by sravan kumar </script> |
Output
5 6 8 9
Complexity Analysis:
- Time Complexity: O(n^2), where n is an order of the given square matrix.
- Auxiliary Space: O(1), as we are not using any extra space.