97 lines
1.7 KiB
Go
97 lines
1.7 KiB
Go
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bufio"
|
||
|
|
"fmt"
|
||
|
|
"math"
|
||
|
|
"os"
|
||
|
|
)
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
content := returnContent("../input")
|
||
|
|
|
||
|
|
//content := returnContent("testInput")
|
||
|
|
|
||
|
|
oxygen, carbon := findOxygenAndCarbon(content, 0)
|
||
|
|
|
||
|
|
fmt.Println(oxygen, carbon)
|
||
|
|
|
||
|
|
fmt.Println(binaryToInteger(oxygen) * binaryToInteger(carbon))
|
||
|
|
}
|
||
|
|
|
||
|
|
func findOxygenAndCarbon(content *[]string, i int) (oxygen string, carbon string) {
|
||
|
|
//recursion
|
||
|
|
|
||
|
|
oxygen = (*findValues(content, 0, true))[0]
|
||
|
|
|
||
|
|
carbon = (*findValues(content, 0, false))[0]
|
||
|
|
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
//recursively find the values that fit the criteria
|
||
|
|
func findValues(content *[]string, i int, inclusive bool) (values *[]string) {
|
||
|
|
|
||
|
|
if len(*content) <= 1 {
|
||
|
|
return content
|
||
|
|
}
|
||
|
|
|
||
|
|
count := 0
|
||
|
|
var bit byte = '0'
|
||
|
|
for j := 0; j < len(*content); j++ {
|
||
|
|
if ((*content)[j])[i] == '1' {
|
||
|
|
count++
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if inclusive {
|
||
|
|
if float64(count) >= float64(len(*content))/2 {
|
||
|
|
bit = '1'
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
if float64(count) < float64(len(*content))/2 {
|
||
|
|
bit = '1'
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
var newContent []string
|
||
|
|
for j := 0; j < len(*content); j++ {
|
||
|
|
if ((*content)[j])[i] == bit {
|
||
|
|
newContent = append(newContent, (*content)[j])
|
||
|
|
}
|
||
|
|
}
|
||
|
|
i++
|
||
|
|
return findValues(&newContent, i, inclusive)
|
||
|
|
}
|
||
|
|
|
||
|
|
func binaryToInteger(input string) (value int) {
|
||
|
|
n := 0
|
||
|
|
for i := len(input) - 1; i >= 0; i-- {
|
||
|
|
if input[i] == '1' {
|
||
|
|
value += (int(math.Pow(float64(2), float64(n))))
|
||
|
|
}
|
||
|
|
n++
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
func returnContent(path string) *[]string {
|
||
|
|
//read file and return it as an array of integers
|
||
|
|
|
||
|
|
file, err := os.Open(path)
|
||
|
|
var content []string
|
||
|
|
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println("Unlucky, the file didn't open")
|
||
|
|
return &content
|
||
|
|
}
|
||
|
|
defer file.Close()
|
||
|
|
|
||
|
|
scanner := bufio.NewScanner(file)
|
||
|
|
for scanner.Scan() {
|
||
|
|
content = append(content, scanner.Text())
|
||
|
|
}
|
||
|
|
|
||
|
|
return &content
|
||
|
|
}
|