Problem of the day
The name of the cake should start with 'c', 'a', 'k', 'e', or 's'.
No two cakes should begin with the same letter.
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"}.
The first line contains an integer 'T', which denotes the number of test cases.
For every test case:-
The first line contains only one integer 'N' the number of cakes.
The second line contains 'N' space-separated strings denoting the elements of the 'S'.
For each test case, return the number of ways to choose three cakes irrespective of the order.
You don’t need to print anything. Just implement the given function.
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
1
0
'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.
2
5
apple kesar strawberry peach almond
1
apple
2
0