Commit 98b1ebc

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Amogh Singhal

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Create maximum_subarray_sum.py

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	`1`	`+# Problem: Given a list of positive and negative numbers, find the maximum subarray sum.`
	`2`	`+# Constraint: Solve it in O(n)`
	`3`	`+`
	`4`	`+# Solution: Use two variables to hold sums`
	`5`	`+# a. overall sum -- initialize to first element`
	`6`	`+# b. partial sum -- initialize to first element`
	`7`	`+# Traverse over the whole array`
	`8`	`+# If the current element is greater than partial sum, swap the partial sum with the current element`
	`9`	`+# If the partial sum is greater than overall sum, swap overall with partial sum`
	`10`	`+# the overall sum will be the contiguous subarray with the largest sum`
	`11`	`+`
	`12`	`+def maxSubArraySum(arr):`
	`13`	`+ max_so_far = arr[0]`
	`14`	`+ current_max = arr[0]`
	`15`	`+`
	`16`	`+ for i in range(1,len(arr)):`
	`17`	`+ current_max = max(arr[i], current_max + arr[i])`
	`18`	`+ max_so_far = max(max_so_far, current_max)`
	`19`	`+`
	`20`	`+ return max_so_far`
	`21`	`+`
	`22`	`+sampleArr = [-2, -3, 4, -1, -2, 1, 5, -3]`
	`23`	`+`
	`24`	`+solution = maxSubArraySum(sampleArr)`
	`25`	`+print(solution)`

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