adventofcode/2020/day01.go

package main

import (
	"fmt"
	"os"

	"git.annabunch.es/annabunches/adventofcode/2020/lib/util"
)

func main() {
	step := os.Args[1]
	values := util.InputParserIntMap(os.Args[2])

	switch step {
	case "1":
		for x, _ := range values {
			if _, ok := values[2020-x]; ok {
				answer := x * (2020 - x)
				fmt.Println("The answer is:", answer)
				return
			}
		}
	case "2":
		for x, _ := range values {
			target := 2020 - x
			for y, _ := range values {
				if _, ok := values[target-y]; ok {
					answer := x * y * (target - y)
					fmt.Println("The answer is:", answer)
					return
				}
			}
		}
	}
}