aoc2024/day-13/internal/one/solve.go
2024-12-13 20:36:10 +00:00

39 lines
724 B
Go

package one
import (
"bytes"
"math"
log "github.com/sirupsen/logrus"
"github.com/onyx-and-iris/aoc2024/day-13/internal/util"
)
func Solve(buf []byte) (int, error) {
r := bytes.NewReader(buf)
machines, err := util.ParseLines(r)
if err != nil {
return 0, err
}
var total int
for _, m := range machines {
denominator := m.A.X*m.B.Y - m.B.X*m.A.Y
a_numerator := m.Prize.X*m.B.Y - m.Prize.Y*m.B.X
b_numerator := m.Prize.Y*m.A.X - m.Prize.X*m.A.Y
a := float64(a_numerator) / float64(denominator)
b := float64(b_numerator) / float64(denominator)
if a != math.Round(a) || a < 0 || b != math.Round(b) || b < 0 {
continue
}
log.Debug(a, b)
total += 3*int(a) + int(b)
}
return total, nil
}