Submission #1990696

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Source Code Expand

from itertools import permutations
n = int(input())
c = [int(input()) for _ in range(n)]
p = list(permutations(c))

ans = 0
for x in c:
    a = sum([x % y == 0 for y in c])
    if a % 2 == 0:
        ans += 1 / 2
    else:
        ans += (a + 1) / (2 * a)
print(ans)

"""
# 99点の全数え上げver.
omote = 0.0
for l in p:
    k = [True for _ in range(len(l))]
    for i, v in enumerate(l):
        for j in range(i + 1, len(l)):
            if l[j] % v == 0:
                k[j] = not k[j]
    omote += k.count(True)
print(omote / len(p))
"""

Submission Info

Judge Result