Feat: 48. Rotate Image

Author: HC-kang

rotate-image/HC-kang.ts

@@ -0,0 +1,22 @@
+/**
+ * https://leetcode.com/problems/rotate-image
+ * T.C. O(n^2)
+ * S.C. O(1)
+ */
+function rotate(matrix: number[][]): void {
+  const n = matrix.length;
+
+  // transpose
+  for (let i = 0; i < n; i++) {
+    for (let j = i; j < n; j++) {
+      [matrix[i][j], matrix[j][i]] = [matrix[j][i], matrix[i][j]];
+    }
+  }
+
+  // reverse
+  for (let i = 0; i < n; i++) {
+    for (let j = 0; j < n / 2; j++) {
+      [matrix[i][j], matrix[i][n - j - 1]] = [matrix[i][n - j - 1], matrix[i][j]];
+    }
+  }
+}