21 lines
856 B
Python
21 lines
856 B
Python
import operator
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def generate_decreasing_n_sequence_with_bounded_sum(sequence_length, sum_bound, value_bound=float('inf')):
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if sequence_length == 0:
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yield []
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return
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min_remaining = sequence_length*(sequence_length - 1)/2
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bound_for_current = min(sum_bound - min_remaining, value_bound)
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for value in range(sequence_length, bound_for_current):
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for sequence in generate_decreasing_n_sequence_with_bounded_sum(sequence_length - 1, sum_bound - value, value_bound=value):
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yield [value] + sequence
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def build_products_to_sequences_map():
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product_to_sequences_map = {}
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for sequence in generate_decreasing_n_sequence_with_bounded_sum(4, 18):
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product = reduce(operator.mul, sequence, 1)
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product_to_sequences_map.setdefault(product, []).append(sequence)
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return product_to_sequences_map
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