In this shot, we will go over how to find the transpose of a [two-dimensional array (matrix)](https://www.educative.io/answers/two-dimensional-arrays-in-c).

# What is the transpose of a matrix?
The **transpose of a matrix** is taken by switching the columns and rows of a matrix. Specifically, the matrix is flipped along its diagonal. The diagonal will remain the same.

# Explanation of the code:
Since we are using a *2-D array*, we need to use a nested `for` loop to traverse through it.
1. First, initialize your 2-D array.
2. Run a nested `for` loop. The outer `for` loop will iterate through rows and the inner loop will iterate through columns.
3. While accessing element `arr[row][col]`, insert the element into `transpose[col][row]`, i.e., switch the rows and columns. For example,      
`arr[0][1]` will be placed at `transpose[1][0]`, so two and four will swap positions in the transpose matrix.
4. The `for` loop will iterate through every element and insert it into the correct index in the `transpose` 2-D array.


#include<iostream>
using namespace std;

// user defined function to print 2 day array with correct format
void printArr (int arr[][3], int columns)
{
    for(int i = 0; i < 3; i++)
    {
        for(int j = 0; j < columns; j++)
        {
            cout << arr[i][j] << " ";
        }
        cout << endl;
    }
}

int main()

{
    // declare matrix
	const int rows = 3;
	const int columns = 3;
	int arr[rows][columns] = {1, 2, 3,
                              4, 5, 6, 
                              7, 8, 9};
    // declare transpose matrix of same size                       
    int transpose[rows][columns];


	cout << "Original Matrix: " << endl;
	printArr(arr, columns);

    // outer for loop to traverse rows
	for(int i = 0; i < rows; i++)
    {
        // inner for loop to traverse column
        for(int j = 0; j < columns; j++)
        {
            // insert arr[row][col] to transpose[col][row]
            transpose[j][i] = arr[i][j];
        }

    }

	cout<< "Transpose Matrix: " << endl;
	printArr(transpose, columns);

return 0;
}


How to find transpose of a 2D Matrix in C++

Switch rows and columns using nested loops to find the transpose of a 2D matrix in C++.