30 lines
898 B
Ruby
30 lines
898 B
Ruby
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# Algorithm to find the largest possible continuos sum in an array.
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#Time-complexity: O(n), Auxiliary space: O(1)
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# Algorithm-paradigm: Dynamic-programming
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# This algorithm doesn't work for negative numbers,it simply returns zero if all numbers are negative.
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def max_continuos_sum(a)
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max_ending_sum = max_slice_sum =0
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n=a.length
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for i in 0...n
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max_ending_sum = [0,(max_ending_sum+a[i])].max
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max_slice_sum = [max_slice_sum,max_ending_sum].max
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end
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return max_slice_sum
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end
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max_continuos_sum([1,1,-1,2,3,4,-9,3,4,5,-6]) # => 13
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# Algorithm to handle negative numbers as well
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def max_continuos_sum(a)
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max_ending_sum = max_slice_sum =a[0]
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n=a.length
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for i in 0...n
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max_ending_sum = [a[i],(max_ending_sum+a[i])].max
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max_slice_sum = [max_slice_sum,max_ending_sum].max
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end
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return max_slice_sum
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end
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max_continuos_sum([-5,-4,-10,-2,-3,-2,-1,-9]) #=> -1
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