43 lines
780 B
Python
43 lines
780 B
Python
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def main():
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n = int(input())
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fa = [int(i)-1 for i in input().split()]
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est_feuille = [True for _ in range(n)]
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for i in range(n):
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if fa[i] != i:
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est_feuille[fa[i]] = False
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f_count = 0
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for i in range(n):
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if est_feuille[i]:
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f_count += 1
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print(f_count)
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used = set()
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def find_path(s):
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l = []
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length = 0
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while s not in used:
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l.append(s)
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used.add(s)
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length += 1
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s = fa[s]
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return reversed(l), length
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paths = []
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for i in range(n):
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if est_feuille[i]:
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p, n = find_path(i)
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print(n)
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print(" ".join([str(i+1) for i in p]))
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print()
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for _ in range(int(input())):
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main()
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