48 lines
995 B
Python
48 lines
995 B
Python
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#!/usr/bin/env python3
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import sys
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import math
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def three_way_partition(A, begin, end):
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i = 0
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j = end - 2
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p = end - 1
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while i < j:
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print(A[begin:i], A[i:j+1], A[j+1:p], A[p:end])
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if A[i] == A[p]:
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p = p - 1
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A[i], A[p] = A[p], A[i]
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if j == p:
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j = j - 1
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elif A[j] == A[p]:
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p = p - 1
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A[j], A[p] = A[p], A[j]
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if j == p:
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j = j - 1
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elif A[i] < A[p]:
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i = i + 1
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elif A[j] > A[p]:
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j = j - 1
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else:
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A[i], A[j] = A[j], A[i]
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m = end - 1
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while i < p:
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print(A)
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A[i], A[m] = A[m], A[i]
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m = m - 1
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i = i + 1
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return [j, m + 1]
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if __name__ == "__main__":
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A = []
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for line in sys.stdin:
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line = line.strip()
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if line == '' or line == '\n':
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break
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A.append(int(line))
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print(three_way_partition(A, 0, len(A)))
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print(A)
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