Definition of Recursion:
- Recursion is a method that calls itself.
- A method is recursive when it contains a call to itself.
Classic Example:
Factorial calculation is a classic example of recursion.
The factorial of a number? is the product of all integers from 1 to N
Code Example:
- Code provided shows a recursive method (factR) and an iterative method (factI) to calculate the factorial.
- Both methods return the same results, but with different approaches.
Working of the Recursive Method:
- The recursive method (factR) calls itself until the value of
- ? n be 1.
- With each recursive call, the method "stacks" and only starts returning when the base condition is met.
Call Stack:
- Each recursive call allocates space on the execution stack for new parameters and variables.
- Recursive calls can cause stack overrun, resulting in exceptions.
Comparison with Iteration:
- Recursive methods may be clearer and simpler for certain algorithms, such as quick sort.
- However, recursive versions may be slower due to method call overhead.
Care when Using Recursion:
- It is crucial to have a termination condition to prevent the method from entering an infinite loop.
- Debug statements such as println() can help you understand the flow of recursive execution.
Recursive Code to Calculate the Factorial
SEE RECURSION.JAVA
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