Why does we consider taking 0 as a subarray

#1

Why can’t we ignore it and just start with the first element

#2

yes
the remainder can be from 0 to n-1
but we have n+1 different elements
so one should definitely same after taking mod with n

#3

but peigon hole principle me to holes kum hote he aur elements jyada right?

#4

yeah sorry it was done by mistake

#5

acha okay . Jab me csum%n krta hu to remainder 0 bhi aa sakta he and if don’t take null subarray to meri number of possibilities kum ho jaengi right?

#6

yes
the remainder can be from 0 to n-1
but we have n+1 different elements
so one should definitely same after taking mod with n

#7

like array is 1 2 2 6 4.
then cumulative array will be- 1 3 5 11 15
so if i do csum%n…then my new array will be- 1 3 0 1 0
so agar me null subarray nhi leta to ans inspite of 3c2 will be 2c2 right?

#8

yes it is correct

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