56 lines
965 B
Go
56 lines
965 B
Go
package main
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import (
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"AoC2020/helper"
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"errors"
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"fmt"
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"os"
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"sort"
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)
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func main() {
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args := os.Args[1:]
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input, err := helper.GetInput(args[0])
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fmt.Println(input)
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if err != nil {
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fmt.Println(err)
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}
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numbers, err := helper.MapToNumber(input)
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if err != nil {
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fmt.Println(err)
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}
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fmt.Println(day1(numbers, 2020))
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fmt.Println(day1_part2(numbers))
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}
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func day1(numbers []int, goal int) int {
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add1, add2, err := helper.FindAddendsForSum(numbers,goal)
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if err != nil {
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return 0
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}
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return add1 * add2
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}
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func day1_part2(numbers []int) (int, error) {
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goal := 2020
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sort.Ints(numbers)
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for i, number := range numbers {
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p1 := i + 1
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p2 := len(numbers) - 1 - i
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for p1 < p2 {
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if numbers[p1]+numbers[p2]+number < goal {
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p1++
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}
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if numbers[p1]+numbers[p2]+number > goal {
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p2--
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}
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if numbers[p1]+numbers[p2]+number == goal {
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return numbers[p1] * numbers[p2] * number, nil
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}
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}
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}
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return 0, errors.New("No Triplet Found")
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}
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