add Spiral Matrix solution

Author: HoonDongKang

spiral-matrix/HoonDongKang.ts

@@ -0,0 +1,39 @@
+/**
+ * [Problem]: [54] Spiral Matrix
+ * (https://leetcode.com/problems/spiral-matrix/description/)
+ */
+function spiralOrder(matrix: number[][]): number[] {
+    const result: number[] = [];
+    let top = 0;
+    let bottom = matrix.length - 1;
+    let left = 0;
+    let right = matrix[0].length - 1;
+
+    while (top <= bottom && left <= right) {
+        for (let i = left; i <= right; i++) {
+            result.push(matrix[top][i]);
+        }
+        top++;
+
+        for (let i = top; i <= bottom; i++) {
+            result.push(matrix[i][right]);
+        }
+        right--;
+
+        if (top <= bottom) {
+            for (let i = right; i >= left; i--) {
+                result.push(matrix[bottom][i]);
+            }
+            bottom--;
+        }
+
+        if (left <= right) {
+            for (let i = bottom; i >= top; i--) {
+                result.push(matrix[i][left]);
+            }
+            left++;
+        }
+    }
+
+    return result;
+}