[20250613] BOJ / G3 / 텀 프로젝트 / 김수연

suyeun84/202506/13 BOJ G3 텀 프로젝트.md

@@ -0,0 +1,48 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class boj9466 {
+	static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+	static StringTokenizer st;
+	static void nextLine() throws Exception {st = new StringTokenizer(br.readLine());}
+	static int nextInt() {return Integer.parseInt(st.nextToken());}
+
+	static int N, cycle;
+	static int[] point;
+	static boolean[] check, visited;
+	public static void main(String[] args) throws Exception {
+		nextLine();
+		int T = nextInt();
+
+		for (int tc = 0; tc < T; tc++) {
+			nextLine();
+			N = nextInt();
+			nextLine();
+			point = new int[N+1];
+			for (int i = 1; i <= N; i++) point[i] = nextInt();
+			cycle = 0;
+			check = new boolean[N+1];
+			visited = new boolean[N+1];
+
+			for (int i = 1; i <= N; i++) {
+				if (check[i]) continue;
+				dfs(i);
+			}
+			System.out.println(N - cycle);
+		}
+
+	}
+	static void dfs(int idx) {
+		if (check[idx]) return;
+		if (visited[idx]) {
+			check[idx] = true;
+			cycle++;
+		}
+		visited[idx] = true;
+		dfs(point[idx]);
+		check[idx] = true;
+		visited[idx] = false;
+	}
+}
+```