Freshman's Database

import sys

if __name__ == '__main__':
    n = int(sys.stdin.readline().strip())

    values = sys.stdin.readline().strip().split()
    visited = [False]*n

    count = 0
    for i in range(n):
        if not visited[i]:
            j = i
            start = i

            while True:
                if not visited[j]:
                    visited[j] = True
                    j = int(values[j].strip()) - 1
                else:
                    if start is j:
                        count += 1
                    break
    print(count)

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER