78 lines
1.1 KiB
Go
78 lines
1.1 KiB
Go
package main
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import (
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"bufio"
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"fmt"
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"os"
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"strconv"
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"time"
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)
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func mustAtoi(line string) int {
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i, _ := strconv.Atoi(line)
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return i
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}
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func main() {
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start := time.Now()
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partOne()
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duration := time.Since(start)
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fmt.Printf("p1: %s\n", duration)
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}
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func makeScanner(test bool) *bufio.Scanner {
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var f *os.File
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if test {
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f, _ = os.Open("inputs/testinput")
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} else {
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f, _ = os.Open("inputs/input")
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}
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reader := bufio.NewReader(f)
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return bufio.NewScanner(reader)
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}
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func parseSNAFU(str string) int {
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num := 0
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place := 1
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for i := len(str) - 1; i >= 0; i-- {
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switch str[i] {
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case '2':
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num += place * 2
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case '1':
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num += place
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case '0':
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// noop
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case '-':
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num -= place
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case '=':
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num -= place * 2
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default:
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panic("oh no")
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}
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place *= 5
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}
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return num
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}
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func toSNAFU(normal int) string {
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num := ""
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digits := []string{"0", "1", "2", "=", "-"}
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for {
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num = digits[normal%5] + num
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if normal == 0 {
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return num
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}
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normal = (normal + 2) / 5
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}
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}
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func partOne() {
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scanner := makeScanner(false)
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sum := 0
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for scanner.Scan() {
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line := scanner.Text()
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sum += parseSNAFU(line)
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}
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fmt.Println(toSNAFU(sum)[1:])
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}
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