//go:build ignore

package main

import (
	"fmt"
	"os"
	"strconv"
)

func fib(x int) int {
	if x < 2 {
		return x
	}
	return fib(x-1) + fib(x-2)
}

var n = 35

func main() {
	if len(os.Args) > 2 {
		n, _ = strconv.Atoi(os.Args[1])
	}
	fmt.Println(fib(n))
}