add Course Schedule solution

Author: HoonDongKang

course-schedule/HoonDongKang.ts

@@ -0,0 +1,42 @@
+/**
+ * [Problem]: [207] Course Schedule
+ * (https://leetcode.com/problems/course-schedule/description/)
+ */
+
+function canFinish(numCourses: number, prerequisites: number[][]): boolean {
+    // 시간복잡도 O(n+m)
+    // 공간복잡도 O(n+m)
+    function graphFunc(numCourses: number, prerequisites: number[][]): boolean {
+        const graph: number[][] = Array.from({ length: numCourses }, () => []);
+
+        for (const [course, prerequisite] of prerequisites) {
+            graph[prerequisite].push(course);
+        }
+
+        let traversing = new Array(numCourses).fill(false);
+        let visited = new Array(numCourses).fill(false);
+
+        function dfs(course: number): boolean {
+            if (traversing[course]) return false;
+            if (visited[course]) return true;
+
+            traversing[course] = true;
+            for (let pre of graph[course]) {
+                if (!dfs(pre)) {
+                    return false;
+                }
+            }
+
+            traversing[course] = false;
+            visited[course] = true;
+            return true;
+        }
+
+        for (let i = 0; i < numCourses; i++) {
+            if (!visited[i] && !dfs(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
+}