rcol := uint16(cdat[6*x+0])<<8 | uint16(cdat[6*x+1])
					gcol := uint16(cdat[6*x+2])<<8 | uint16(cdat[6*x+3])
					bcol := uint16(cdat[6*x+4])<<8 | uint16(cdat[6*x+5])
					rgba64.SetRGBA64(x, y, color.RGBA64{rcol, gcol, bcol, 0xffff})
				}
			}
		case cbTCA16:
			for x := 0; x < width; x++ {
				rcol := uint16(cdat[8*x+0])<<8 | uint16(cdat[8*x+1])
				gcol := uint16(cdat[8*x+2])<<8 | uint16(cdat[8*x+3])

	release := make(chan int)
	go dosplit(in, out, release)
	dat := <-in.dat
	out[0].dat <- dat
	if !both {
		<-wait
	}
	<-out[1].req
	out[1].dat <- dat
	release <- 0
}

func split(in *dch, out *dch2) {
	release := make(chan int)
	go dosplit(in, out, release)
	release <- 0
}

func put(dat item, out *dch) {
	<-out.req
	out.dat <- dat
}

func get(in *dch) *rat {
	seqno++

	release := make(chan int)
	go dosplit(in, out, release)
	dat := <-in.dat
	out[0].dat <- dat
	if !both {
		<-wait
	}
	<-out[1].req
	out[1].dat <- dat
	release <- 0
}

func split(in *dch, out *dch2) {
	release := make(chan int)
	go dosplit(in, out, release)
	release <- 0
}

func put(dat rat, out *dch) {
	<-out.req
	out.dat <- dat
}

func get(in *dch) rat {
	seqno++

	cdat2 := cr[2][1:]
	cdat3 := cr[3][1:]
	cdat4 := cr[4][1:]
	pdat := pr[1:]
	n := len(cdat0)

	// The up filter.
	sum := 0
	for i := 0; i < n; i++ {
		cdat2[i] = cdat0[i] - pdat[i]
		sum += abs8(cdat2[i])
	}
	best := sum
	filter := ftUp

	// The Paeth filter.
	sum = 0
	for i := 0; i < bpp; i++ {
		cdat4[i] = cdat0[i] - pdat[i]
		sum += abs8(cdat4[i])
	}
	for i := bpp; i < n; i++ {

import (
	"fmt"
	"math"
)

// A Rat represents a quotient a/b of arbitrary precision.
// The zero value for a Rat represents the value 0.
//
// Operations always take pointer arguments (*Rat) rather
// than Rat values, and each unique Rat value requires
// its own unique *Rat pointer. To "copy" a Rat value,
// an existing (or newly allocated) Rat must be set to
// a new value using the [Rat.Set] method; shallow copies

// when simply accessing the Rat value.
func TestIssue34919(t *testing.T) {
	for _, acc := range []struct {
		name string
		f    func(*Rat)
	}{
		{"Float32", func(x *Rat) { x.Float32() }},
		{"Float64", func(x *Rat) { x.Float64() }},
		{"Inv", func(x *Rat) { new(Rat).Inv(x) }},
		{"Sign", func(x *Rat) { x.Sign() }},
		{"IsInt", func(x *Rat) { x.IsInt() }},
		{"Num", func(x *Rat) { x.Num() }},

		{data: dat, off: 0, n: len(dat), bufLen: len(dat) / 2, at: 0, exp: dat[:len(dat)/2], err: nil},
		{data: dat, off: 0, n: len(dat), bufLen: len(dat), at: 0, exp: dat, err: nil},
		{data: dat, off: 0, n: len(dat), bufLen: len(dat) / 2, at: 2, exp: dat[2 : 2+len(dat)/2], err: nil},
		{data: dat, off: 3, n: len(dat), bufLen: len(dat) / 2, at: 2, exp: dat[5 : 5+len(dat)/2], err: nil},

	un0 := un10 & mask32
	q1 := un32 / yn1
	rhat := un32 - q1*yn1

	for q1 >= two32 || q1*yn0 > two32*rhat+un1 {
		q1--
		rhat += yn1
		if rhat >= two32 {
			break
		}
	}

	un21 := un32*two32 + un1 - q1*y
	q0 := un21 / yn1
	rhat = un21 - q0*yn1

	for q0 >= two32 || q0*yn0 > two32*rhat+un0 {
		q0--
		rhat += yn1
		if rhat >= two32 {
			break
		}
	}

	un0 := un10 & (1<<32 - 1)
	q1 := un32 / vn1
	rhat := un32 - q1*vn1

again1:
	if q1 >= b || q1*vn0 > b*rhat+un1 {
		q1--
		rhat += vn1
		if rhat < b {
			goto again1
		}
	}

	un21 := un32*b + un1 - q1*v
	q0 := un21 / vn1
	rhat = un21 - q0*vn1

again2:
	if q0 >= b || q0*vn0 > b*rhat+un0 {
		q0--
		rhat += vn1
		if rhat < b {
			goto again2
		}
	}

			}
		}
	}
}

func TestRatSetStringZero(t *testing.T) {
	got, _ := new(Rat).SetString("0")
	want := new(Rat).SetInt64(0)
	if !reflect.DeepEqual(got, want) {
		t.Errorf("got %#+v, want %#+v", got, want)
	}
}

func TestRatScan(t *testing.T) {
	var buf bytes.Buffer
	for i, test := range setStringTests {
		x := new(Rat)
		buf.Reset()
		buf.WriteString(test.in)

		_, err := fmt.Fscanf(&buf, "%v", x)