45 lines
1.6 KiB
Python
45 lines
1.6 KiB
Python
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from SoSe24.algodat.foundation import AlgoDatArray, AlgoDatValue, read_int_sequence, MinusInf
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from time import perf_counter as pfc
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def in_between(z: AlgoDatArray, l: int, m: int, r: int) -> (AlgoDatValue, int, int):
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left_max = AlgoDatValue(MinusInf())
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left = AlgoDatValue(0)
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current_sum = AlgoDatValue(0)
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for i in range(m, l - 1, -1):
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current_sum += z[i]
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if current_sum > left_max:
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left_max.value = current_sum.value
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left.value = i
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right_max = AlgoDatValue(MinusInf())
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right = AlgoDatValue(0)
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current_sum.value = 0
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for i in range(m + 1, r + 1):
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current_sum += z[i]
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if current_sum > right_max:
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right_max.value = current_sum.value
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right.value = i
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return left_max + right_max, left, right
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def maxfolge_part(z: AlgoDatArray, l:int, r:int) -> (int, int, int):
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if l == r:
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return z[l].value, l, r
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m = (l + r) // 2
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left_sum, left_left, left_right = maxfolge_part(z, l, m)
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right_sum, right_left, right_right = maxfolge_part(z, m + 1, r)
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cross_sum, cross_left, cross_right = in_between(z, l, m, r)
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if left_sum >= right_sum and left_sum >= cross_sum:
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return left_sum, left_left, left_right
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elif right_sum >= left_sum and right_sum >= cross_sum:
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return right_sum, right_left, right_right
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else:
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return cross_sum, cross_left, cross_right
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def maxfolge3(z: AlgoDatArray) -> (int, int, int):
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return maxfolge_part(z, 0, z.size - 1)
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if __name__ == "__main__":
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z = read_int_sequence("../../seq3.txt")
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start = pfc()
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print(maxfolge3(z))
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print(f"Dauer: {pfc() - start:.4f}s")
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AlgoDatValue.summary()
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