Home>

What do you mean (;;)

The recursive data type A * of the alphabet set A is defined as follows:

Basic case

A * contains the empty character λ

Configuration case

If a ∈ A, s ∈ A * then the pair ∈ A *

Related questions

- about the problem of c language recursion
- recursion - whether it is in tail-recursive form
- python - atcoder abc138d dfs
- display from the value entered in the recursive function to 0 using the relational reference
- java - recursive sample code decoding
- python 3x - program errors related to recursive and dynamic programming algorithms
- python 3x - about the method of thinking about the algorithm of dynamic programming from the algorithm of power leaving
- python - time complexity of the program that calls the function
- python 3x - euclid mutual division method with and without recursive expression time order (order)
- c ++ - i want to display the minimum number of moves on the tower of hanoi

The recursive definition is the definition of the starting point (in the case of a question, the basic case "A * contains the empty character λ") and the definition of how to extend it. (In the case of a question, it consists of a configuration case "a ∈ A * if a ∈ A, s ∈ A *").

Suppose that the alphabet set A contains three alphabets 'A', 'B', and 'C'.

I will represent it as ['A', 'B', 'C'].

And then

-Set A * containing only λ is a recursive data type of set A (base case): A * can be expressed as [λ].

-The set [λ, 'A'] with 'A' added to it includes the pair<λ, 'A'>(configuration case).

・ Furthermore, in the set [λ, 'A', 'B'] with 'B' added, the pairs<λ, 'A'>and<λ, 'B'>and<'A', 'B'>And<λ, 'A', 'B'>are included.

So the recursive data type A * can be extended and reconstructed,

[λ]

[λ, 'A']

[λ, 'B']

[λ, 'C']

[λ, 'A', 'B']

[λ, 'A', 'C']

[λ, 'B', 'C']

[λ, 'A', 'B', 'C']

Can be either.