package main

import (
	"fmt"
	"io/ioutil"
	"strconv"
	"strings"
)

func main() {
	data, _ := ioutil.ReadFile("in1.txt")
	s := strings.Split(string(data), "\n")
	var nums []int
	for _, st := range s {
		n, _ := strconv.Atoi(st)
		nums = append(nums, n)
	}
	for _, n := range nums {
		for _, n2 := range nums {
			if n2 != n {
				for _, n3 := range nums {
					if n != n3 && n2 != n3 {
						if n+n2+n3 == 2020 {
							fmt.Println(n * n2 * n3)
							return
						}
					}
				}
			}
		}
	}
}