Given an grid of letters, one can select four squares such that the first is a C
,
the second is an A
, the third is an L
, and the last is an I
, and two adjacent squares in the pattern
share at least a corner.
This selection process is repeated as many times as possible, with the caveat that a given square can only be selected at most once.
Compute the maximum number of distinct sets of letters that can be selected.
Constraints
In tests worth marks, you may assume .
In tests worth an additional marks, you may assume .
Input Specification
The first line of the input contains a single integer, .
The next lines contain characters, all of which appear in CALI
.
Output Specification
Output, on a single line, the maximum number of sets that can be selected.
Sample Input
4
CALI
ILAC
CLLC
IAAI
Sample Output
4
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