给定一个 n × n 的二维矩阵 matrix
表示一个图像。请你将图像顺时针旋转 90 度。
你必须在 原地 旋转图像,这意味着你需要直接修改输入的二维矩阵。请不要 使用另一个矩阵来旋转图像。
示例 1:
输入:matrix = [[1,2,3],[4,5,6],[7,8,9]] 输出:[[7,4,1],[8,5,2],[9,6,3]]
示例 2:
输入:matrix = [[5,1,9,11],[2,4,8,10],[13,3,6,7],[15,14,12,16]] 输出:[[15,13,2,5],[14,3,4,1],[12,6,8,9],[16,7,10,11]]
示例 3:
输入:matrix = [[1]] 输出:[[1]]
示例 4:
输入:matrix = [[1,2],[3,4]] 输出:[[3,1],[4,2]]
提示:
matrix.length == n
matrix[i].length == n
1 <= n <= 20
-1000 <= matrix[i][j] <= 1000
class Solution:
def rotate(self, matrix: List[List[int]]) -> None:
"""
Do not return anything, modify matrix in-place instead.
"""
s, n = 0, len(matrix)
while s < (n >> 1):
e = n - s - 1
for i in range(s, e):
t = matrix[i][e]
matrix[i][e] = matrix[s][i]
matrix[s][i] = matrix[n - i - 1][s]
matrix[n - i - 1][s] = matrix[e][n - i - 1]
matrix[e][n - i - 1] = t
s += 1
class Solution {
public void rotate(int[][] matrix) {
int s = 0, n = matrix.length;
while (s < (n >> 1)) {
int e = n - s - 1;
for (int i = s; i < e; ++i) {
int t = matrix[i][e];
matrix[i][e] = matrix[s][i];
matrix[s][i] = matrix[n - i - 1][s];
matrix[n - i - 1][s] = matrix[e][n - i - 1];
matrix[e][n - i - 1] = t;
}
++s;
}
}
}