37 lines
586 B
Python
37 lines
586 B
Python
#!/usr/bin/env python
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def p(n,k):
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if k == 0:
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return 0
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elif n == k or k == 1:
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return 1
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elif n < k:
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return 0
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else:
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return p(n-1,k-1) + p(n-k,k)
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def s(n,k):
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if n == k:
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return 1
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elif k == 0:
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return 0
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elif n < k:
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return 0
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else:
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return s(n-1,k-1) + (n-1)*s(n-1,k)
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def S(n, k):
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if n == k:
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return 1
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elif k == 1:
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return 1
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elif k == 0:
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return 0
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elif n < k:
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return 0
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else:
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return S(n-1,k-1) + k * S(n-1,k)
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# print(S(9,5))
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print(p(10,4))
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