I'm studying Java and I need to do a recursive Fibonacci program, but I have no idea how to do this. Please, if you know, help me. Here is an inductive code:
public static void main(String[] args) {
int n = 5, i = 0, a = 0, b = 1;
System.out.print( a + " " + b + " ");
while(i<=n){
int c = a + b;
System.out.print(c + " ");
a = b;
b = c;
i++;
}
}
The recursive call to Fibonacci is quite simple:
class Fibonacci {
public static long fibonacci(int n) {
return n < 2 ? n : fibonacci(n - 2) + fibonacci(n - 1);
}
public static void main(String[] args) {
for (int i = 0; i <= 10; i++) {
System.out.println("Fibonacci(" + i + ") = " + fibonacci(i));
}
}
}
Here's the output:
Fibonacci(0) = 0
Fibonacci(1) = 1
Fibonacci(2) = 1
Fibonacci(3) = 2
Fibonacci(4) = 3
Fibonacci(5) = 5
Fibonacci(6) = 8
Fibonacci(7) = 13
Fibonacci(8) = 21
Fibonacci(9) = 34
Fibonacci(10) = 55
However, Fibonacci is a classic example of a problem where using recursion is a very bad strategy and performs poorly. The use by iteration (with while or for ) is much higher. See more details on this on this other answer of mine .