Related Articles

# Interchange elements of first and last columns in matrix

• Difficulty Level : Easy
• Last Updated : 19 Apr, 2021

Given a 4 x 4 matrix, the task is to interchange the elements of first and last columns and show the resulting matrix.
Examples:

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

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

The approach is very simple, we can simply swap the elements of first and last column of the matrix in order to get the desired matrix as output.
Below is the implementation of the above approach :

## C++

 `// C++ code to swap the element of first``// and last column and display the result``#include ``using` `namespace` `std;` `#define n 4` `void` `interchangeFirstLast(``int` `m[][n])``{``    ``// swapping of element between first``    ``// and last columns``    ``for` `(``int` `i = 0; i < n; i++) {``        ``int` `t = m[i][0];``        ``m[i][0] = m[i][n - 1];``        ``m[i][n - 1] = t;``    ``}``}` `// Driver function``int` `main()``{``    ``// input in the array``    ``int` `m[n][n] = { { 8, 9, 7, 6 },``                    ``{ 4, 7, 6, 5 },``                    ``{ 3, 2, 1, 8 },``                    ``{ 9, 9, 7, 7 } };` `    ``interchangeFirstLast(m);` `    ``// printing the interchanged matrix``    ``for` `(``int` `i = 0; i < n; i++) {``        ``for` `(``int` `j = 0; j < n; j++)``            ``cout << m[i][j] << ``" "``;``        ``cout << endl;``    ``}``}`

## Java

 `// Java code to swap the element of first``// and last column and display the result` `import` `java.io.*;` `class` `GFG {``   ` `static` `int` `n = ``4``;` `static` `void` `interchangeFirstLast(``int` `m[][])``{``    ``int` `cols = n;` `    ``// swapping of element between first``    ``// and last columns``    ``for` `(``int` `i = ``0``; i < n; i++) {``        ``int` `t = m[i][``0``];``        ``m[i][``0``] = m[i][n - ``1``];``        ``m[i][n - ``1``] = t;``    ``}``}` `// Driver function` `    ``public` `static` `void` `main (String[] args) {``            ``// input in the array``    ``int` `m[][] = { { ``8``, ``9``, ``7``, ``6` `},``                    ``{ ``4``, ``7``, ``6``, ``5` `},``                    ``{ ``3``, ``2``, ``1``, ``8` `},``                    ``{ ``9``, ``9``, ``7``, ``7` `} };` `    ``interchangeFirstLast(m);` `    ``// printing the interchanged matrix``    ``for` `(``int` `i = ``0``; i < n; i++) {``        ``for` `(``int` `j = ``0``; j < n; j++)``            ``System.out.print(m[i][j] + ``" "``);``            ``System.out.println();``    ``}``    ``}``}``// This code is contributed by inder_verma`

## Python 3

 `# Python3 code to swap the element of``# first and last column and display``# the result``  ` `def` `interchangeFirstLast(mat, n, m):``    ``rows ``=` `n``      ` `    ``# swapping of element between``    ``# first and last columns``    ``for` `i ``in` `range``(n):``            ``t ``=` `mat[i][``0``];``            ``mat[i][``0``] ``=` `mat[i][n``-``1``];``            ``mat[i][n``-``1``] ``=` `t;``  ` `# Driver Program``mat ``=` `[[``8``, ``9``, ``7``, ``6``],``       ``[``4``, ``7``, ``6``, ``5``],``       ``[``3``, ``2``, ``1``, ``8``],``       ``[``9``, ``9``, ``7``, ``7``]]``  ` `n ``=` `4``m ``=` `4``interchangeFirstLast(mat, n, m)``  ` `# printing the interchanged matrix``for` `i ``in` `range``(n):``    ``for` `j ``in` `range``(m):``        ``print``(mat[i][j], end ``=` `" "``)``    ``print``(``"\n"``)`

## C#

 `// C# code to swap the element of first``// and last column and display the result``using` `System;` `class` `GFG``{``    ` `static` `int` `n = 4;` `static` `void` `interchangeFirstLast(``int``[, ] m)``{``    ``int` `cols = n;` `    ``// swapping of element between first``    ``// and last columns``    ``for` `(``int` `i = 0; i < n; i++)``    ``{``        ``int` `t = m[i, 0];``        ``m[i, 0] = m[i, n - 1];``        ``m[i, n - 1] = t;``    ``}``}` `// Driver Code``public` `static` `void` `Main ()``{``// input in the array``int``[,] m = { { 8, 9, 7, 6 },``                ``{ 4, 7, 6, 5 },``                ``{ 3, 2, 1, 8 },``                ``{ 9, 9, 7, 7 } };` `interchangeFirstLast(m);` `// printing the interchanged matrix``for` `(``int` `i = 0; i < n; i++)``{``    ``for` `(``int` `j = 0; j < n; j++)``        ``Console.Write(m[i, j] + ``" "``);``        ``Console.WriteLine();``}``}``}` `// This code is contributed``// by Akanksha Rai`

## PHP

 ``

## Javascript

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

Attention reader! Don’t stop learning now. Participate in the Scholorship Test for First-Step-to-DSA Course for Class 9 to 12 students.

My Personal Notes arrow_drop_up