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* fixup! Format Python code with psf/black push * Create codespell.yml * fixup! Format Python code with psf/black push
54 lines
1.5 KiB
Python
54 lines
1.5 KiB
Python
"""
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The stock span problem is a financial problem where we have a series of n daily
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price quotes for a stock and we need to calculate span of stock's price for all n days.
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The span Si of the stock's price on a given day i is defined as the maximum
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number of consecutive days just before the given day, for which the price of the stock
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on the current day is less than or equal to its price on the given day.
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"""
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def calculateSpan(price, S):
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n = len(price)
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# Create a stack and push index of fist element to it
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st = []
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st.append(0)
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# Span value of first element is always 1
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S[0] = 1
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# Calculate span values for rest of the elements
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for i in range(1, n):
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# Pop elements from stack while stack is not
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# empty and top of stack is smaller than price[i]
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while len(st) > 0 and price[st[0]] <= price[i]:
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st.pop()
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# If stack becomes empty, then price[i] is greater
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# than all elements on left of it, i.e. price[0],
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# price[1], ..price[i-1]. Else the price[i] is
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# greater than elements after top of stack
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S[i] = i + 1 if len(st) <= 0 else (i - st[0])
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# Push this element to stack
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st.append(i)
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# A utility function to print elements of array
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def printArray(arr, n):
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for i in range(0, n):
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print(arr[i], end=" ")
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# Driver program to test above function
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price = [10, 4, 5, 90, 120, 80]
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S = [0 for i in range(len(price) + 1)]
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# Fill the span values in array S[]
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calculateSpan(price, S)
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# Print the calculated span values
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printArray(S, len(price))
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