For problem statement at 1000-1999/1900-1999/1920-1929/1928/problemF.txt this is a correct solution, but verifier at 1000-1999/1900-1999/1920-1929/1928/verifierF.go ends with panic: runtime error: index out of range [3] with length 3

goroutine 1 [running]:
main.(*Fenwick).Sum(...)
	/home/ubuntu/codeforces/1000-1999/1900-1999/1920-1929/1928/1928F.go:29
main.contributionB(0x40000a0d58?)
	/home/ubuntu/codeforces/1000-1999/1900-1999/1920-1929/1928/1928F.go:178 +0x1e8
main.addSegmentB(0x4)
	/home/ubuntu/codeforces/1000-1999/1900-1999/1920-1929/1928/1928F.go:218 +0x90
main.main()
	/home/ubuntu/codeforces/1000-1999/1900-1999/1920-1929/1928/1928F.go:326 +0xa44
exit status 2
reference error: exit status 1
exit status 1 can you fix the verifier? ```go
package main

import (
	"io"
	"os"
	"strconv"
)

type FastScanner struct {
	data []byte
	idx  int
	n    int
}

func NewFastScanner() *FastScanner {
	data, _ := io.ReadAll(os.Stdin)
	return &FastScanner{data: data, n: len(data)}
}

func (fs *FastScanner) NextInt64() int64 {
	for fs.idx < fs.n && fs.data[fs.idx] <= ' ' {
		fs.idx++
	}
	sign := int64(1)
	if fs.data[fs.idx] == '-' {
		sign = -1
		fs.idx++
	}
	var val int64
	for fs.idx < fs.n {
		c := fs.data[fs.idx]
		if c < '0' || c > '9' {
			break
		}
		val = val*10 + int64(c-'0')
		fs.idx++
	}
	return sign * val
}

type Fenwick struct {
	n    int
	tree []int64
}

func NewFenwick(n int) Fenwick {
	if n < 1 {
		n = 1
	}
	return Fenwick{n: n, tree: make([]int64, n+1)}
}

func (f *Fenwick) Add(i int, delta int64) {
	for i <= f.n {
		f.tree[i] += delta
		i += i & -i
	}
}

func (f *Fenwick) Sum(i int) int64 {
	if i > f.n {
		i = f.n
	}
	var res int64
	for i > 0 {
		res += f.tree[i]
		i -= i & -i
	}
	return res
}

func (f *Fenwick) Kth(k int64) int {
	idx := 0
	step := 1
	for (step << 1) <= f.n {
		step <<= 1
	}
	for step > 0 {
		next := idx + step
		if next <= f.n && f.tree[next] < k {
			idx = next
			k -= f.tree[next]
		}
		step >>= 1
	}
	return idx + 1
}

type Dim struct {
	n         int
	diff      []int64
	bad       []bool
	badBIT    Fenwick
	totBad    int64
	lenCnt    Fenwick
	lenS1     Fenwick
	lenS2     Fenwick
	lenS3     Fenwick
	totBlocks int64
}

func NewDim(vals []int64, n int) *Dim {
	d := &Dim{
		n:      n,
		diff:   make([]int64, n+1),
		bad:    make([]bool, n+1),
		badBIT: NewFenwick(n - 1),
		lenCnt: NewFenwick(n),
		lenS1:  NewFenwick(n),
		lenS2:  NewFenwick(n),
		lenS3:  NewFenwick(n),
	}
	prev := 0
	for i := 1; i < n; i++ {
		d.diff[i] = vals[i] - vals[i+1]
		if d.diff[i] == 0 {
			d.bad[i] = true
			d.badBIT.Add(i, 1)
			d.totBad++
			d.addLen(i - prev)
			prev = i
		}
	}
	d.addLen(n - prev)
	return d
}

func (d *Dim) addLen(l int) {
	x := int64(l)
	x2 := x * x
	d.lenCnt.Add(l, 1)
	d.lenS1.Add(l, x)
	d.lenS2.Add(l, x2)
	d.lenS3.Add(l, x2*x)
	d.totBlocks++
}

func (d *Dim) removeLen(l int) {
	x := int64(l)
	x2 := x * x
	d.lenCnt.Add(l, -1)
	d.lenS1.Add(l, -x)
	d.lenS2.Add(l, -x2)
	d.lenS3.Add(l, -x2*x)
	d.totBlocks--
}

func (d *Dim) Contribution(s int) int64 {
	if s <= 0 {
		return 0
	}
	x := s - 1
	cL := d.lenCnt.Sum(x)
	sumL := d.lenS1.Sum(x)
	sum2L := d.lenS2.Sum(x)
	sum3L := d.lenS3.Sum(x)
	cR := d.totBlocks - cL
	sumR := int64(d.n) - sumL
	S := int64(s)
	six := 3*S*(sum2L+sumL) + (sumL - sum3L) + 3*S*(S+1)*sumR + (S-S*S*S)*cR
	return six / 6
}

func (d *Dim) prevSepBefore(i int) int {
	cnt := d.badBIT.Sum(i - 1)
	if cnt == 0 {
		return 0
	}
	return d.badBIT.Kth(cnt)
}

func (d *Dim) nextSepAfter(i int) int {
	cnt := d.badBIT.Sum(i)
	if cnt == d.totBad {
		return d.n
	}
	return d.badBIT.Kth(cnt + 1)
}

func (d *Dim) changeEdge(i int, newBad bool, other *Dim) int64 {
	if newBad {
		prev := d.prevSepBefore(i)
		next := d.nextSepAfter(i)
		whole := next - prev
		left := i - prev
		right := next - i
		delta := -other.Contribution(whole) + other.Contribution(left) + other.Contribution(right)
		d.removeLen(whole)
		d.addLen(left)
		d.addLen(right)
		d.bad[i] = true
		d.badBIT.Add(i, 1)
		d.totBad++
		return delta
	}
	prev := d.prevSepBefore(i)
	next := d.nextSepAfter(i)
	left := i - prev
	right := next - i
	delta := -other.Contribution(left) - other.Contribution(right) + other.Contribution(left+right)
	d.removeLen(left)
	d.removeLen(right)
	d.addLen(left + right)
	d.bad[i] = false
	d.badBIT.Add(i, -1)
	d.totBad--
	return delta
}

func (d *Dim) applyEdgeDelta(i int, delta int64, other *Dim) int64 {
	oldBad := d.bad[i]
	d.diff[i] += delta
	newBad := d.diff[i] == 0
	if oldBad == newBad {
		return 0
	}
	return d.changeEdge(i, newBad, other)
}

func (d *Dim) ApplyRange(l, r int, x int64, other *Dim) int64 {
	var delta int64
	if l > 1 {
		delta += d.applyEdgeDelta(l-1, -x, other)
	}
	if r < d.n {
		delta += d.applyEdgeDelta(r, x, other)
	}
	return delta
}

func main() {
	fs := NewFastScanner()
	n := int(fs.NextInt64())
	m := int(fs.NextInt64())
	q := int(fs.NextInt64())

	a := make([]int64, n+1)
	b := make([]int64, m+1)

	for i := 1; i <= n; i++ {
		a[i] = fs.NextInt64()
	}
	for i := 1; i <= m; i++ {
		b[i] = fs.NextInt64()
	}

	rows := NewDim(a, n)
	cols := NewDim(b, m)

	var ans int64
	prev := 0
	for i := 1; i < n; i++ {
		if rows.bad[i] {
			ans += cols.Contribution(i - prev)
			prev = i
		}
	}
	ans += cols.Contribution(n - prev)

	out := make([]byte, 0, (q+1)*24)
	out = strconv.AppendInt(out, ans, 10)
	out = append(out, '\n')

	for ; q > 0; q-- {
		t := int(fs.NextInt64())
		l := int(fs.NextInt64())
		r := int(fs.NextInt64())
		x := fs.NextInt64()
		if t == 1 {
			ans += rows.ApplyRange(l, r, x, cols)
		} else {
			ans += cols.ApplyRange(l, r, x, rows)
		}
		out = strconv.AppendInt(out, ans, 10)
		out = append(out, '\n')
	}

	os.Stdout.Write(out)
}
```