次はUCLAで読んだCS 32:Data Structuresの記事です.

📝 Recursion

Rules

Every recursive function must have a stopping condition (base case).

Recursive functions should never use global, static, or member variables. They should only use local variables and parameters.

Steps

1. Write the function header.
Figure out what arguments your function will take and what it needs to return.
2. Define your magic function.
Magic function here shows logic behind the recursive function. Before making a recursive function right away, write magic function.
3. Add your base case code.
There might be multiple base cases for a function depending on what it does.
4. Solve the problem by using the magic function.
Divide the problem into sub parts and arrange what the magic function returns
5. Remove the magic function.
6. Validate function with the simplest possible input, then more complex inputs.

Class Challenge

printArr

void printArr(int arr[], int size) 
{
	if (size == 0)
    	cout << *arr << "\n";
    printArr(arr+1, size-1);
}

reversePrint

void reversePrint(string arr[], int size)
{
	if (size == 0) 
    	cout << arr[0] << "\n";
   	reversePrint(arr+1, size-1);
}

Recursion with Linked List

Tips

Your recursive function should generally only access the current node/array cell passed into it.
Your recursive function should rarely/never access the values in the node/cell below it.