Score : 300 points
There are N people. The name of the i-th person is S_i.
We would like to choose three people so that the following conditions are met:
M, A, R, C or H.How many such ways are there to choose three people, disregarding order?
Note that the answer may not fit into a 32-bit integer type.
Input is given from Standard Input in the following format:
N S_1 : S_N
If there are x ways to choose three people so that the given conditions are met, print x.
5 MASHIKE RUMOI OBIRA HABORO HOROKANAI
2
We can choose three people with the following names:
MASHIKE, RUMOI, HABORO
MASHIKE, RUMOI, HOROKANAI
Thus, we have two ways.
4 ZZ ZZZ Z ZZZZZZZZZZ
0
Note that there may be no ways to choose three people so that the given conditions are met.
5 CHOKUDAI RNG MAKOTO AOKI RINGO
7