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Spiral Matrix

Question​

What is the most efficient way to traverse a given NxN matrix in a spiral pattern?

Example 1
Input: 
4

Output: 
[
 [ 1,  2,  3, 4],
 [12, 13, 14, 5],
 [11, 16, 15, 6],
 [10,  9,  8, 7]
]

Solution​

all//Spiral Matrix.py


def spiral_matrix(m, n, a) :
    k = 0; l = 0

    ''' k - starting row index 
        m - ending row index 
        l - starting column index 
        n - ending column index 
        i - iterator '''


    while (k < m and l < n) :

        # Print the first row from
        # the remaining rows
        for i in range(l, n) :
            print(a[k][i], end = " ")

        k += 1

        # Print the last column from
        # the remaining columns
        for i in range(k, m) :
            print(a[i][n - 1], end = " ")

        n -= 1

        # Print the last row from
        # the remaining rows
        if ( k < m) :

            for i in range(n - 1, (l - 1), -1) :
                print(a[m - 1][i], end = " ")

            m -= 1

        # Print the first column from
        # the remaining columns
        if (l < n) :
            for i in range(m - 1, k - 1, -1) :
                print(a[i][l], end = " ")

            l += 1