1260. Shift 2D Grid

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

In one shift operation:

• Element at grid[i][j] moves to grid[i][j + 1].
• Element at grid[i][n - 1] moves to grid[i + 1][0].
• Element at grid[m - 1][n - 1] moves to grid[0][0].

Return the 2D grid after applying shift operation k times.

class Solution {
public:
    vector<vector<int>> shiftGrid(vector<vector<int>>& g, int k) {
        int n = g.size(), m = g[0].size();
        k %= m * n;
        k = m * n - k;
        vector<vector<int>> res(n, vector<int>(m));
        for(int i = 0; i < n*m; i++) {
            int y = i / m, x = i % m;
            int ty = ((i + k) % (m * n)) / m, tx = ((i + k) % (m * n)) % m;
            res[y][x] = g[ty][tx];
        }
        return res;
    }
};