Python/dynamic_programming/longest_sub_array.py

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"""
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Auther : Yvonne
2017-01-09 18:44:48 +00:00
This is a pure Python implementation of Dynamic Programming solution to the longest_sub_array problem.
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The problem is :
Given an array, to find the longest and continuous sub array and get the max sum of the sub array in the given array.
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"""
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class SubArray:
def __init__(self, arr):
# we need a list not a string, so do something to change the type
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self.array = arr.split(",")
print(("the input array is:", self.array))
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def solve_sub_array(self):
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rear = [int(self.array[0])] * len(self.array)
sum_value = [int(self.array[0])] * len(self.array)
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for i in range(1, len(self.array)):
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sum_value[i] = max(
int(self.array[i]) + sum_value[i - 1], int(self.array[i])
)
rear[i] = max(sum_value[i], rear[i - 1])
return rear[len(self.array) - 1]
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if __name__ == "__main__":
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whole_array = input("please input some numbers:")
array = SubArray(whole_array)
re = array.solve_sub_array()
print(("the results is:", re))