Why is FAANG Asking Such an EASY Coding Question? | Running Sum of 1d Array - Leetcode 1480

dynamic programming, leetcode, coding interview question, data structures, data structures and algorithms, faang

[GregHogg]

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[comedyclub]

"First, I'm gonna import pandas"...

[WifeWantsAWizard]

Part of the test is naming conventions. naming your temp variables something like "currentSum" instead of "s" is important.

[SirBearingtonSupporter]

def running_sum(nums):
sum = 0
return [(sum := sum + val) for val in nums]

[donwald]

Are you serious, on phone screens I ask "in any programming language, determine the length of a string" and approximately 1/50 resume-screened candidates say anything remotely sensible lol.

[hughjwoods]

If you're using a language with a scan function it can be even simpler. E.g. in Scala
val nums = List(1, 2, 3, 4)
nums.scan(0)(_ + _).tail

[TreeLuvBurdpu]

Wouldn't you want to yield the sum at each iteration to make it "running"?

[abdulamite]

You can flex and even do it in O(1) space if you wanna be fancy

[evancourtney]

If the numbers will always be evenly spaced you could use the Gauss method to find the sum of any sub array of arbitrary length, no need to to keep a running total.

[donfeto]

nums = [1, 2, 3, 4]

Result = [0]*len(nums)
Result[0] = 1
for i in range(1, len(nums)):
Result[i] = Result[i-1] + nums[i]

print(Result)

[helensirani]

Can you recommend great online platform to learn data structure and algorithms to get at equipt to answer these interview questions?

[datadecks]

Why a list and not initialize the array with the same size as the input array that you want to cumulative sum over

[tm-luk]

What is the name of the software he uses as a blackboard?

[jeffmejia]

where do i find this kind of questions?

[tennicktenstyl]

just run it on the GPU split the array and put in multi threaded addition on CUDA

[suic]

from itertools import accumulate

result = list(accumulate(arr)) # 😂

[eclipsesword]

What if I want to modify nums instead of creating a new array?

[vishalsrivastava]

Iterate from index 1 update index I with index I + index i-1

[AllanSavolainen]

Why wouldn't you allocated the sums[] to have as many items as nums? Now you are dynamically growing it while adding the sums...

[frstchan]

Everything is easy if you practiced first.