Print N*N spiral matrix

Print N*N spiral matrix:

Given a number n, print a n x n spiral matrix (of numbers from 1 to n x n) in clockwise direction using O(1) space.

Input: n = 5

Output:
25 24 23 22 21
10  9  8  7 20
11  2  1  6 19
12  3  4  5 18
13 14 15 16 17

CODE: 

// C++ program to print a n x n spiral matrix 

// in clockwise direction using O(1) space 

#include <bits/stdc++.h> 

using namespace std;

// Prints spiral matrix of size n x n containing

// numbers from 1 to n x n

void printSpiral(int n)

{

    for (int i = 0; i < n; i++)

    {

        for (int j = 0; j < n; j++)

        {

            // x stores the layer in which (i, j)th

            // element lies

            int x;

 

            // Finds minimum of four inputs

            x = min(min(i, j), min(n-1-i, n-1-j));

 

            // For upper right half

            if (i <= j)

                printf("%2d ", (n-2*x)*(n-2*x) - (i-x)

                       - (j-x));

 

            // for lower left half

            else

                printf("%2d ", (n-2*x-2)*(n-2*x-2) + (i-x)

                       + (j-x));

        }

        printf("\n");

    }

}

// Driver code
int main()
{
    int n = 5;
 
    // print a n x n spiral matrix in O(1) space
    printSpiral(n);
 
    return 0;
}
//credits: geeksforgeeks