I am trying to implement this code and this website has kindly provided their algorithm but I am trying to Find out what is "N" I understood what "I" and "M" is but not "N", is "N" the Total input(in the below example 5 because there are 5 letters)?
Algorithm:
Combinations are generated in lexicographical order. The algorithm uses indexes of the elements of the set. Here is how it works on example: Suppose we have a set of 5 elements with indexes 1 2 3 4 5 (starting from 1), and we need to generate all combinations of size m
= 3.
First, we initialize the first combination of size m – with indexes in ascending order
1 2 3
Then we check the last element (i = 3). If its value is less than n – m + i, it is incremented by 1.
1 2 4
Again we check the last element, and since it is still less than n – m
- i, it is incremented by 1.
1 2 5
Now it has the maximum allowed value: n – m + i = 5 – 3 + 3 = 5, so we move on to the previous element (i = 2).
If its value less than n – m + i, it is incremented by 1, and all following elements are set to value of their previous neighbor plus 1
1 (2+1)3 (3+1)4 = 1 3 4
Then we again start from the last element i = 3
1 3 5
Back to i = 2
1 4 5
Now it finally equals n – m + i = 5 – 3 + 2 = 4, so we can move to first element (i = 1) (1+1)2 (2+1)3 (3+1)4 = 2 3 4
And then,
2 3 5
2 4 5
3 4 5
- and it is the last combination since all values are set to the maximum possible value of n – m + i.
Input:
A
B
C
D
E
Output:
A B C
A B D
A B E
A C D
A C E
A D E
B C D
B C E
B D E
C D E
>Solution :
Take a look at the very first paragraf of the link you provided.
It states that
This combinations calculator generates all possible combinations of m elements from the set of n elements.
So yes, n is the number of elements or letters that the algorithm needs to use.