Matrix Boundary Traversal
EasyP3Coding
matrix is an N x N matrix. Return its boundary elements in clockwise order, starting at the bottom-left corner: go up the first column, then right along the top row, then down the last column, then left along the bottom row, stopping before the starting corner. Every boundary element appears exactly once.
For a 1 x 1 matrix the answer is its single element.
Example 1
- Input
- matrix = [[1,2,3],[4,5,6],[7,8,9]]
- Output
- [7,4,1,2,3,6,9,8]
Example 2
- Input
- matrix = [[1,2],[3,4]]
- Output
- [3,1,2,4]
Example 3
- Input
- matrix = [[5]]
- Output
- [5]
Constraints
- 1 <= N <= 100
- -10^9 <= matrix[i][j] <= 10^9
Hints
Give it a real attempt first. Run shows which examples fail.
Saved automatically
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