Submission #3617107

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Source Code Expand

import sys
n = int(input())
a = list(map(int, input().split()))

a.sort()
ra = a.copy()
a = a[0::2]
ra = ra[1::2]
ra.reverse()
a = ra + a
for i in range(n):
    if a[i] != abs(n - 1 - i * 2):
        print(0)
        sys.exit(0)
print(2 ** (n // 2) % 1000000007)

Submission Info

Compile Error

./Main.cpp:1:1: error: ‘import’ does not name a type
 import sys
 ^