leetcode

commit f3112ac70d2216bb1091ebb4fb3634a87a1efda2
parent eab73660e5f82bd021bac7afac5287c62827e0ec
Author: Dimitrije Dobrota <mail@dimitrijedobrota.com>
Date:   Mon,  6 Feb 2023 16:49:45 +0100

Data Structure II: Day 3

Diffstat:
A
Problems/0048.cpp
 | 
17
+++++++++++++++++
M
README.md
 | 
1
+

2 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/Problems/0048.cpp b/Problems/0048.cpp
@@ -0,0 +1,17 @@
+class Solution {
+  typedef vector<vector<int>> Mat;
+  int n;
+
+  void swap_group(Mat &matrix, int x, int y) {
+    swap(matrix[x][y], matrix[y][n - x - 1]);
+    swap(matrix[n - x - 1][n - y - 1], matrix[n - y - 1][x]);
+    swap(matrix[x][y], matrix[n - x - 1][n - y - 1]);
+  }
+
+public:
+  void rotate(Mat &matrix) {
+    n = matrix.size();
+    for (int i = 0; i <= n / 2; i++)
+      for (int j = i; j < n - i - 1; j++) swap_group(matrix, i, j);
+  }
+};
diff --git a/README.md b/README.md
@@ -51,6 +51,7 @@ for solving problems.
 |  0043  |   Medium   | [Multiply Strings](Problems/0043.cpp)                                                            |
 |  0045  |   Medium   | [Jump Game II](Problems/0045.cpp)                                                                |
 |  0046  |   Medium   | [Permutations](Problems/0046.cpp)                                                                |
+|  0048  |   Medium   | [Rotate Image](Problems/0048.cpp)                                                                |
 |  0049  |   Medium   | [Group Anagrams](Problems/0049.cpp)                                                              |
 |  0053  |   Medium   | [Maximum Subarray](Problems/0053.cpp)                                                            |
 |  0054  |   Medium   | [Spiral Matrix](Problems/0054.cpp)                                                               |