1+ import java .io .*;
2+ import java .util .*;
3+ 4+ //2 ≤ n ≤ 10^5
5+ public class YJ_9466 {
6+ static int [] graph ;
7+ static boolean [] visited ;
8+ static boolean [] isFinished ;
9+ static boolean [] isGrouping ;
10+ 11+ public static void main (String [] args ) throws IOException {
12+ BufferedReader br = new BufferedReader (new InputStreamReader (System .in ));
13+ StringTokenizer st = new StringTokenizer (br .readLine ());
14+ int T = Integer .parseInt (st .nextToken ());
15+ 16+ //테스트케이스 실행
17+ while (T -- > 0 ){
18+ //초기화
19+ int n = Integer .parseInt (br .readLine ());
20+ graph = new int [n +1 ];
21+ isFinished = new boolean [n +1 ];
22+ visited = new boolean [n +1 ];
23+ isGrouping = new boolean [n +1 ];
24+ st = new StringTokenizer (br .readLine ());
25+ for (int i =1 ; i <n +1 ; i ++){
26+ graph [i ] = Integer .parseInt (st .nextToken ());
27+ }
28+ //dfs 탐색
29+ for (int i =1 ; i <n +1 ; i ++){
30+ if (!visited [i ]){
31+ dfs (i );
32+ }
33+ }
34+ //프로젝트 팀에 속하지 못한 학생 수
35+ int count = 0 ;
36+ for (int i =1 ; i <n +1 ; i ++){
37+ if (!isGrouping [i ]){
38+ count ++;
39+ }
40+ }
41+ System .out .println (count );
42+ }
43+ 44+ }
45+ 46+ public static void dfs (int current ){
47+ visited [current ] = true ;
48+ int next = graph [current ];
49+ 50+ if (!visited [next ]){
51+ dfs (next );
52+ } else if (!isFinished [next ]) { //★재방문이지만 이전에 사이클을 이미 만들었거나, 사이클 형성을 못한 경우
53+ //싸이클 형성 가능 또는 자기자신
54+ while (!isGrouping [next ]){
55+ isGrouping [next ] = true ;
56+ next = graph [next ];
57+ }
58+ }
59+ isFinished [current ] = true ;
60+ }
61+ 62+ }
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