package main

import (
	"bufio"
	"fmt"
	"log"
	"math"
	"os"
	"strconv"
)

func main() {
	inp := StdinToStringSlice()
	fmt.Println("Fuel Required:", part1(inp))
}

func part1(inp []string) int {
	var total int
	for _, v := range inp {
		total = total + part2(fuelRequired(float64(Atoi(v))))
	}
	return total
}

func part2(fuel int) int {
	ret := fuel
	for fuel > 0 {
		fuel = fuelRequired(float64(fuel))
		fmt.Println(fuel)
		ret = ret + fuel
	}
	return ret
}

func fuelRequired(mass float64) int {
	res, _ := math.Modf(mass / 3)
	if int(res)-2 < 0 {
		return 0
	}
	return int(res) - 2
}

func StdinToStringSlice() []string {
	var input []string
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		input = append(input, scanner.Text())
	}
	return input
}

func Atoi(i string) int {
	var ret int
	var err error
	if ret, err = strconv.Atoi(i); err != nil {
		log.Fatal("Invalid Atoi")
	}
	return ret
}