﻿EXTERN FUNCTION Main(args[])
    VARIABLE result = Fibonacci(9)
    System.Console.WriteLine("Fib 9 = " + result)
    RETURN result
END FUNCTION

FUNCTION Fibonacci(n)
    # To return the first Fibonacci number
    IF n = 0 THEN
        RETURN 0
    END IF

    VARIABLE a = 0
    VARIABLE b = 1
    VARIABLE c = 0
    VARIABLE i = 2

    DO WHILE i <= n
        c = a + b
        a = b
        b = c
        i = i + 1
    LOOP

    RETURN b
END FUNCTION