class Fib { static function fib1(n : int) : int { if (n <= 2) return 1; else return Fib.fib1(n - 1) + Fib.fib1(n - 2); } static function fib2(n : number) : number { return n <= 2 ? 1 : Fib.fib2(n - 1) + Fib.fib2(n - 2); } static function fib3(n : int) : int { if (n <= 2) return 1; var value = 1; var prevValue = 1; for (var i = 3; i <= n; i++) { var t = value + prevValue; prevValue = value; value = t; } return value; } static function fib4(n : int) : int { switch (n) { case 1: case 2: return 1; default: return Fib.fib4(n - 1) + Fib.fib4(n - 2); } } static function fib5(n : int, a : int = 1, b : int = 1) : int { switch (n) { case 1: case 2: return a; default: return Fib.fib5(n - 1, a + b, a); } } } class _Main { static function main(args : string[]) : void { var n = args.length> 0 ? args[0] as number : 10; log "fib1(" + n as string + ") = " + Fib.fib1(n) as string; log "fib2(" + n as string + ") = " + Fib.fib2(n) as string; log "fib3(" + n as string + ") = " + Fib.fib3(n) as string; log "fib4(" + n as string + ") = " + Fib.fib4(n) as string; log "fib5(" + n as string + ") = " + Fib.fib5(n) as string; } }