Divisible subarrays (Challenges Number Theory)

#1

Hey
So after watching the concept of divisble arrays i tried to code it own my own before watching the actual code video

But only two test cases are running fine , for two exclamation mark is coming and for one wrong answer

#2

hello @nischay1111
a) use long long in place of int.
b) use modular arithmetic while permforming addition
i,e (a+b)%mod =(a%mod+b%mod)%mod
c) dont use factorical . it might cause overflow.
nc2=n*(n-1)/2 so use this formula in place of factorial.

#3

hey i made the changes suggested but stll showing exclamation for three test cases

#4


here is the link to the new changed code

#5

finally modified code according to the video
still two test cases not passing

#6

@nischay1111

image

replace this line with.
sum=(sum+a[i])%n

#7

Thanks
though i was able to solve the problem with your help
But when i was writing in line 22
sum+=a[i]
then in the next line i was also doing
sum=(sum+n)%n

so how is changing line 22 with sum=(sum+a[i])%n making a difference ?

#8

sum+a[i] might oveflow so was taking % n to avoid it.

refer this article-> https://www.hackerearth.com/practice/math/number-theory/basic-number-theory-1/tutorial/

#9

okay
thanks a lot for the help

#10

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