28 lines
489 B
Python
28 lines
489 B
Python
import sys
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T = int(sys.stdin.readline())
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P = [2]
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K = [0] * 1000005
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K[2] = True
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for i in range(2, 1000000 - 1):
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for p in P:
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if i % p == 0:
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break
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elif p * p > i:
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P.append(i)
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K[i] = 1
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break
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else:
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P.append(i)
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K[i] = 1
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break
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for _ in range(T):
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n = int(sys.stdin.readline())
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c = 0
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for i in range(2, n//2+1):
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if K[i] and K[n - i]:
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c += 1
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i += 1
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print(c)
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