set
answer
Solution only requires one set Laid
Like the same song into the array like
$(sum[r]-sum[l])\%n==0$
Split into $ sum [r] \% n == sum [l] \% n $ bucket deposit $ sum [l] \% n $ $ sum find each [R & lt] $ bucket has no corresponding #sum [ l] #
Deposit $ tong [0] = 1 $, the other first check deposit
prove
Prove correctness
Their legitimate $ 0 $ $ (sum [r] \% n) == 0 $ need not find the corresponding
The other is to find a match
Suppose we have $ n + 1 $ a $ sum '$ value (assumed here $ sum [0] $ is also looking for a match)
$ \ $ SUM runs over the range of $ $ [0, n-1] the significance% n $ $
$ N + 1 $ a $ sum $, $ n $ types of values must have a legitimate
It may therefore permit