Example: Fibonacci Sequence

FibonacciNumbersDemo.java

/**
 * Example: Fibonacci Sequence
 * In mathematics, the Fibonacci numbers, commonly denoted Fn, form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1.
 * Reference: https://en.wikipedia.org/wiki/Fibonacci_number
 * Sample Series: 0	1	1	2	3	5	8	13	21	34	55	89	144	233	377	610	987	1597	2584	4181
 * */
public class FibonacciNumbersDemo {
    public static void main(String[] args) {
        int f0, f1, fn;
        int num = 20;
        f0=0;
        f1=1;
        for (int i = 0;i<num;i++){
//            if(i==0){
//                fn=f0+f0;
//            }
//            else if(i==1){
//                fn=f1+f0;
//                f1=fn;
//
//            }
//            else{
//                fn=f1+f0;
//                f0=f1;
//                f1=fn;
//            }
            System.out.print(f0+"\t");
            fn=f0+f1;
            f0=f1;
            f1=fn;
        }
    }
}