90 lines
1.4 KiB
Go
90 lines
1.4 KiB
Go
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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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)
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const entryBits = 12
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//const entryBits = 5
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func nthBit(f int, i int) int {
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a := entryBits - i - 1
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return f & (1 << a) >> a
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}
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type NumberList []int
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func (n NumberList) CountBits(index int) (ones int, zeroes int) {
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for _, num := range n {
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if nthBit(num, index) == 1 {
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ones++
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} else {
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zeroes++
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}
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}
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return
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}
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func (n NumberList) Filter(index int, bit int) NumberList {
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var res NumberList
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for _, num := range n {
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if nthBit(num, index) == bit {
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res = append(res, num)
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}
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}
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return res
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}
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func main() {
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var numbers NumberList
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s := bufio.NewScanner(os.Stdin)
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for s.Scan() {
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value, _ := strconv.ParseInt(s.Text(), 2, 64)
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numbers = append(numbers, int(value))
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}
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oxygenNumbers := numbers
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for i := 0; i < entryBits; i++ {
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ones, zeroes := oxygenNumbers.CountBits(i)
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var bit int
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if ones >= zeroes {
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bit = 1
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} else {
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bit = 0
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}
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//fmt.Println(i, bit, zeroes, ones, len(oxygenNumbers))
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oxygenNumbers = oxygenNumbers.Filter(i, bit)
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if len(oxygenNumbers) == 1 {
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break
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}
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}
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oxygen := oxygenNumbers[0]
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co2Numbers := numbers
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for i := 0; i < entryBits; i++ {
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ones, zeroes := co2Numbers.CountBits(i)
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var bit int
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if ones < zeroes {
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bit = 1
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} else {
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bit = 0
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}
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//fmt.Println(i, bit, zeroes, ones, len(co2Numbers))
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co2Numbers = co2Numbers.Filter(i, bit)
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if len(co2Numbers) == 1 {
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break
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}
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}
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co2 := co2Numbers[0]
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fmt.Println(oxygen * co2)
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}
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