2066: [USACO 2025 US Open Contest, Bronze] Problem 3. It's Mooin' Time III
题目描述
Elsie is trying to describe her favorite USACO contest to Bessie, but Bessie is having trouble understanding why Elsie likes it so much. Elsie says "And It's mooin' time! Who wants a mooin'? Please, I just want to do USACO".
Bessie still doesn't understand, so she transcribes Elsie's description in a string of length ( ) containing lowercase alphabetic characters . Elsie considers a string containing three characters a moo if and .
A triplet is valid if and string forms a moo. For the triplet, FJ performs the following to calculate its value:
- FJ bends string 90-degrees at index
- The value of the triplet is twice the area of .
In other words, the value of the triplet is .
Bessie asks you ( ) queries. In each query, she gives you two integers and ( , ) and ask you for the maximum value among valid triplets such that and . If no valid triplet exists, output .
Note that the large size of integers involved in this problem may require the use of 64-bit integer data types (e.g., a "long long" in C/C++).
输入
The following line contains .
The following lines contain two integers and , denoting each query.
输出
样例输入
12 5
abcabbacabac
1 12
2 7
4 8
2 5
3 10
样例输出
28
6
1
-1
12
提示
For the third query, ( . It can be shown that the maximum area of for some valid ( ) is achieved when , , and .
) must satisfyFor the fourth query, there exists no ( in which is a moo so the output to that query is .
) satisfying