You have 'N' cakes of different names. You want to choose exactly 3 cakes out of these 'N' cakes. The name of the ith cake is 'S[i]' (0 <= i < 'N'). The three chosen cakes should follow the following conditions.
The name of the cake should start with 'c', 'a', 'k', 'e', or 's'.
No two cakes should begin with the same letter.
Return the number of ways to choose three cakes irrespective of the order.
Note : Assume 0-based indexing.
For example:Let 'N' = 4, S = ["choco", "apple", "kesar", "strawberry"].
There exist 4 different ways to choose three cakes following all the required conditions i.e. {"choco", "apple", "kesar"}, {"choco", "apple", "strawberry"}, {"choco", "strawberry", "kesar"}, {"strawberry", "apple", "kesar"}.
1 <= 'T' <= 10
1 <= 'N' <= 10^4
0 <= |S[i]| <= 10
All the names of cakes are distinct and consist of lowercase letters.
Time Limit: 1 sec
2
4
apple kesar strawberry peach
2
apple kesar
Sample Output 1:-
1
0
Explanation of sample input 1:-
'N' = 4, S = ["apple", "kesar", "strawberry", "peach"].
There exists only one way to choose three cakes following all the required conditions i.e. {"strawberry", "apple", "kesar"}. So, the answer is 1.
Second test case:-
'N' = 2, S = ["apple", "kesar"]. As 'N' is less than 3, So there is no way to choose the three cakes. Hence, the answer is 0.
Sample Input 2:-
2
5
apple kesar strawberry peach almond
1
apple
Sample Output 2:-
2
0