59 lines
1.1 KiB
Go
59 lines
1.1 KiB
Go
package main
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import (
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"fmt"
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"log"
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"os"
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"strconv"
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"strings"
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)
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func parseInput(file string) []int {
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content, err := os.ReadFile(file)
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if err != nil {
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log.Fatalf("Failed to read input file: %v", err)
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}
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lines := strings.Fields(string(content))
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var data []int
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for _, line := range lines {
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num, err := strconv.Atoi(line)
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if err != nil {
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log.Fatalf("Failed to convert string to int: %v", err)
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}
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data = append(data, num)
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}
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return data
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}
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func PartOne(data []int) int {
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seen := make(map[int]bool)
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for _, number := range data {
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complement := 2020 - number
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if seen[complement] {
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return number * complement
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}
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seen[number] = true
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}
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return 0
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}
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func PartTwo(data []int) int {
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seen := make(map[int]bool)
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for idx := range data {
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for _, number := range data[idx+1:] {
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complement := 2020 - data[idx] - number
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if seen[complement] {
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return complement * data[idx] * number
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}
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}
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seen[data[idx]] = true
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}
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return 0
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}
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func main() {
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data := parseInput("input.txt")
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fmt.Println("Part 1:", PartOne(data))
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fmt.Println("Part 2:", PartTwo(data))
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}
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