feat(src): add 48-rotate

Author: kwu130

src/48-rotate.cpp

@@ -0,0 +1,61 @@
+//
+// Created by 1412 on 2025/10/28.
+//
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+class Solution {
+public:
+    void rotate(vector<vector<int>>& matrix) {
+        int m = matrix.size();
+        int n = matrix[0].size();
+        for (int i = 0; i < m; i++) {
+            for (int j = i; j < n; j++) {
+                swap(matrix[i][j], matrix[j][i]);  // 转置
+            }
+        }
+        for (int i = 0; i < m; i++) {
+            for (int j = 0; j < n / 2; j++) {
+                swap(matrix[i][j], matrix[i][n - j - 1]);  // 镜像
+            }
+        }
+    }
+};
+
+void test() {
+    Solution s;
+    vector<vector<int>> matrix = {
+        {1, 2, 3},
+        {4, 5, 6},
+        {7, 8, 9}
+    };
+    vector<vector<int>> expected = {
+        {7, 4, 1},
+        {8, 5, 2},
+        {9, 6, 3}
+    };
+    s.rotate(matrix);
+    assert(matrix == expected);
+
+    matrix = {
+        { 5,  1,  9, 11},
+        { 2,  4,  8, 10},
+        {13,  3,  6,  7},
+        {15, 14, 12, 16}
+    };
+    expected = {
+        {15, 13,  2,  5},
+        {14,  3,  4,  1},
+        {12,  6,  8,  9},
+        {16,  7, 10, 11}
+    };
+    s.rotate(matrix);
+    assert(matrix == expected);
+}
+
+int main() {
+    test();
+    return 0;
+}