# C++ Program to Print a given matrix in reverse spiral form

• Last Updated : 10 Jan, 2022

Given a 2D array, print it in reverse spiral form. We have already discussed Print a given matrix in spiral form. This article discusses how to do the reverse printing. See the following examples.

```Input:
1    2   3   4
5    6   7   8
9   10  11  12
13  14  15  16
Output:
10 11 7 6 5 9 13 14 15 16 12 8 4 3 2 1
Input:
1   2   3   4  5   6
7   8   9  10  11  12
13  14  15 16  17  18
Output:
11 10 9 8 7 13 14 15 16 17 18 12 6 5 4 3 2 1```

## C++

 `// This is a modified code of``// https://www.geeksforgeeks.org/print-a-given-matrix-in-spiral-form/``#include ``#define R 3``#define C 6``using` `namespace` `std;`` ` `// Function that print matrix in reverse spiral form.``void` `ReversespiralPrint(``int` `m, ``int` `n, ``int` `a[R][C])``{``    ``// Large array to initialize it``    ``// with elements of matrix``    ``long` `int` `b;``     ` `    ``/* k - starting row index``    ``l - starting column index*/``    ``int` `i, k = 0, l = 0;``     ` `    ``// Counter for single dimension array``    ``//in which elements will be stored``    ``int` `z = 0;``     ` `    ``// Total elements in matrix``    ``int` `size = m*n;`` ` `    ``while` `(k < m && l < n)``    ``{``        ``// Variable to store value of matrix.``        ``int` `val;``         ` `        ``/* Print the first row from the remaining rows */``        ``for` `(i = l; i < n; ++i)``        ``{``            ``// printf("%d ", a[k][i]);``            ``val = a[k][i];``            ``b[z] = val;``            ``++z;``        ``}``        ``k++;`` ` `        ``/* Print the last column from the remaining columns */``        ``for` `(i = k; i < m; ++i)``        ``{``            ``// printf("%d ", a[i][n-1]);``            ``val = a[i][n-1];``            ``b[z] = val;``            ``++z;``        ``}``        ``n--;`` ` `        ``/* Print the last row from the remaining rows */``        ``if` `( k < m)``        ``{``            ``for` `(i = n-1; i >= l; --i)``            ``{``                ``// printf("%d ", a[m-1][i]);``                ``val = a[m-1][i];``                ``b[z] = val;``                ``++z;``            ``}``            ``m--;``        ``}`` ` `        ``/* Print the first column from the remaining columns */``        ``if` `(l < n)``        ``{``            ``for` `(i = m-1; i >= k; --i)``            ``{``                ``// printf("%d ", a[i][l]);``                ``val = a[i][l];``                ``b[z] = val;``                ``++z;``            ``}``            ``l++;``        ``}``    ``}``    ``for` `(``int` `i=size-1 ; i>=0 ; --i)``    ``{``        ``cout<

Output:

`11 10 9 8 7 13 14 15 16 17 18 12 6 5 4 3 2 1`

Please refer complete article on Print a given matrix in reverse spiral form for more details!

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