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Spiral Matrix - Leetcode 54 - Python

 Given an m x n matrix, return all elements of the matrix in spiral order.



Input: matrix = [[1,2,3],[4,5,6],[7,8,9]]
Output: [1,2,3,6,9,8,7,4,5]



class Solution:

    def spiralOrder(self, m: List[List[int]]) -> List[int]:

        ans = []

        l, r = 0, len(m[0])

        t, b = 0, len(m)

        

        while l < r and t < b:

            

            # top row cover

            for i in range(l,r):

                ans.append(m[t][i])

            t += 1


            # right col cover

            for  i in range(t,b):

                ans.append(m[i][r-1])

            r -= 1

            

            # no jhanjat of 1 x n or n x 1 

            if not (l < r and t < b):

                break


            # bottom row cover

            for i in range(r-1,l-1,-1):

                ans.append(m[b-1][i])

            b -= 1


            # left col cover

            for i in range(b-1,t-1,-1):

                ans.append(m[i][l])

            l +=1

            

        return ans



Explaination :











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