EasyNo. 1260

Shift 2D Grid — LeetCode 1260 Python Solution

Topics
Array, Matrix, Simulation
Reading time
2 min

The problem

Given a 2D grid of size m x n and an integer k. You need to shift the grid k times.

Example

Input
grid = [[1,2,3],[4,5,6],[7,8,9]], k = 1
Output
[[9,1,2],[3,4,5],[6,7,8]]

Python solution

PythonSolution
class Solution:
    def shiftGrid(self, grid: List[List[int]], k: int) -> List[List[int]]:
        m, n = len(grid), len(grid[0])
        ans = [[0] * n for _ in range(m)]
        for i, row in enumerate(grid):
            for j, v in enumerate(row):
                x, y = divmod((i * n + j + k) % (m * n), n)
                ans[x][y] = v
        return ans

Complexity

Time
O(m × n)where m and n are the number of rows and columns in the `grid` array, respectively
Space · auxiliary
O(1)

Pattern: Matrix and Grid

Treat a 2-D grid as a graph whose neighbours are the four adjacent cells. LeetCode 1260. Shift 2D Grid is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Matrix.

The matrix and grid guide has the Python template for the pattern and the 216 LeetCode problems that use it.

Related problems

Related problems
No.ProblemDifficulty
0054Spiral MatrixMedium
0059Spiral Matrix IIMedium
0289Game of LifeMedium
0498Diagonal TraverseMedium
0566Reshape the MatrixEasy
0867Transpose MatrixEasy

Frequently asked questions

How hard is LeetCode 1260. Shift 2D Grid?

LeetCode 1260. Shift 2D Grid is rated Easy on LeetCode.

What is the time complexity of LeetCode 1260. Shift 2D Grid?

The Python solution on this page runs in O(m × n), where m and n are the number of rows and columns in the `grid` array, respectively.

What is the space complexity of LeetCode 1260. Shift 2D Grid?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 1260. Shift 2D Grid cover?

LeetCode 1260. Shift 2D Grid is tagged Array, Matrix and Simulation on LeetCode.

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