#P9188. [USACO23OPEN] Pareidolia S

[USACO23OPEN] Pareidolia S

Description

Given a string ss, let B(s)B(s) represent the maximum number of repeated copies of "bessie" one can form by deleting zero or more of the characters from ss. In the example above, B(“bqessiyexbesszieb")=2B(\text{``bqessiyexbesszieb"}) = 2.

Computing B(s)B(s) is an interesting challenge, but Farmer John is interested in solving a challenge that is even more interesting: Given a string tt of length at most 31053\cdot 10^5 consisting only of characters a-z, compute the sum of B(s)B(s) over all contiguous substrings ss of tt.

Input Format

The input consists of a nonempty string of length at most 31053\cdot 10^5 whose characters are all lowercase English letters.

Output Format

Output a single number, the total number of bessies that can be made across all substrings of the input string.

bessiebessie

14

abcdefghssijebessie

28

Hint

For the first sample, twelve substrings contain exactly 11 "bessie", and 11 string contains exactly 22 "bessie"s, so the total is 121+12=1412\cdot 1+1\cdot 2=14.

  • Inputs 3-5: The string has length at most 50005000.
  • Inputs 6-12: No additional constraints.