Let’s learn recursion in java.
Recursion in java
Recursion is a process where a method calls itself infinitely or continuously.
Recursion program
Recursion makes code closely packed and difficult to understand. Here’s an example on infinite recursive function.
public class InfiniteRecursiveExample
{
static void print()
{
System.out.println("helloworld");
print();
}
public static void main(String[] args)
{
print();
}
}
Output:
helloworld
helloworld
helloworld
helloworld………
java.lang.StackOverflowError
Now let’s see an example on finite recursive method.
public class FiniteRecursiveExample
{
static int number = 0;
static void print()
{
number++;
if(number <= 10)
{
System.out.println("helloworld " + number);
print();
}
}
public static void main(String[] args)
{
print();
}
}
Output:
helloworld 1
helloworld 2
helloworld 3
helloworld 4
helloworld 5
helloworld 6
helloworld 7
helloworld 8
helloworld 9
helloworld 10
Fibonacci using recursion : recursion example
public class JavaFibonacciRecursion
{
static int num1 = 0, num2 = 1, num3 = 0;
static void displayFibonacciSeries(int count)
{
if(count > 0)
{
num3 = num1 + num2;
num1 = num2;
num2 = num3;
System.out.print(" " + num3);
displayFibonacciSeries(count - 1);
}
}
public static void main(String[] args)
{
int count = 10;
System.out.print(num1 + " " + num2);
displayFibonacciSeries(count - 2);
}
}
Output:
0 1 1 2 3 5 8 13 21 34
Factorial using recursion : recursion example
public class JavaFactorialRecursion
{
static int printFactorial(int number)
{
if(number == 1)
{
return 1;
}
else
{
return(number * printFactorial(number - 1));
}
}
public static void main(String[] args)
{
System.out.println("Factorial of 6 is : " + printFactorial(6));
}
}
Output:
Factorial of 6 is : 720
Also read – major features of java