package one import ( "bytes" "math" log "github.com/sirupsen/logrus" ) func Solve(buf []byte) (int, error) { r := bytes.NewReader(buf) machines, err := 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 }