Spiral Matrix problem Leet Code

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

Example 1:



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

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

Example 2:



Input: matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]

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

 

class Solution {
    public List<Integer> spiralOrder(int[][] matrix) {
     
            List<Integer> result = new ArrayList<>();
       int rows = matrix.length;
        int cols = matrix[0].length;
        int top = 0, bottom = rows - 1, left = 0, right = cols - 1;

       while (top <= bottom && left <= right) {
            // Move right
            for (int i = left; i <= right; i++) {
                result.add(matrix[top][i]);
            }
            top++;

            // Move down
            for (int i = top; i <= bottom; i++) {
                result.add(matrix[i][right]);
            }
            right--;

            // Move left
            if (top <= bottom) {
                for (int i = right; i >= left; i--) {
                    result.add(matrix[bottom][i]);
                }
                bottom--;
            }

            // Move up
            if (left <= right) {
                for (int i = bottom; i >= top; i--) {
                    result.add(matrix[i][left]);
                }
                left++;
            }
        }
return result;
    }
}

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