For problem statement at 0-999/200-299/210-219/217/problemE.txt this is a correct solution, but verifier at 0-999/200-299/210-219/217/verifierE.go ends with case 1 failed: expected TTAAT got TAT
exit status 1 can you fix the verifier? package main

import (
	"bufio"
	"io"
	"os"
)

const (
	typOrig = 0
	typConcat = 1
	typView = 2
)

type Node struct {
	typ uint8
	len int64
	a   int64
	b   int64
	l   *Node
	r   *Node
}

type Fast struct {
	data []byte
	i    int
	n    int
}

func (f *Fast) skip() {
	for f.i < f.n && f.data[f.i] <= ' ' {
		f.i++
	}
}

func (f *Fast) nextBytes() []byte {
	f.skip()
	start := f.i
	for f.i < f.n && f.data[f.i] > ' ' {
		f.i++
	}
	return f.data[start:f.i]
}

func (f *Fast) nextInt64() int64 {
	f.skip()
	var v int64
	for f.i < f.n && f.data[f.i] > ' ' {
		v = v*10 + int64(f.data[f.i]-'0')
		f.i++
	}
	return v
}

var pool []Node
var poolPtr int

func alloc() *Node {
	n := &pool[poolPtr]
	poolPtr++
	return n
}

func makeOrig(start, step, cnt int64) *Node {
	if cnt <= 0 {
		return nil
	}
	if cnt == 1 {
		step = 1
	}
	n := alloc()
	n.typ = typOrig
	n.len = cnt
	n.a = start
	n.b = step
	n.l = nil
	n.r = nil
	return n
}

func locate(node *Node, pos int64) int64 {
	for {
		switch node.typ {
		case typOrig:
			return node.a + node.b*(pos-1)
		case typView:
			pos = node.a + node.b*(pos-1)
			node = node.l
		default:
			if pos <= node.l.len {
				node = node.l
			} else {
				pos -= node.l.len
				node = node.r
			}
		}
	}
}

func makeView(child *Node, offset, step, cnt int64) *Node {
	if child == nil || cnt <= 0 {
		return nil
	}
	if cnt == 1 {
		return makeOrig(locate(child, offset), 1, 1)
	}
	for {
		if offset == 1 && step == 1 && cnt == child.len {
			return child
		}
		switch child.typ {
		case typOrig:
			return makeOrig(child.a+child.b*(offset-1), child.b*step, cnt)
		case typView:
			offset = child.a + child.b*(offset-1)
			step = child.b * step
			child = child.l
		default:
			lenL := child.l.len
			last := offset + step*(cnt-1)
			if last <= lenL {
				child = child.l
			} else if offset > lenL {
				offset -= lenL
				child = child.r
			} else {
				n := alloc()
				n.typ = typView
				n.len = cnt
				n.a = offset
				n.b = step
				n.l = child
				n.r = nil
				return n
			}
		}
	}
}

func makeConcat(a, b *Node) *Node {
	if a == nil {
		return b
	}
	if b == nil {
		return a
	}
	if a.typ == typOrig && b.typ == typOrig && a.b == b.b && a.a+a.b*a.len == b.a {
		return makeOrig(a.a, a.b, a.len+b.len)
	}
	if a.typ == typView && b.typ == typView && a.l == b.l && a.b == b.b && a.a+a.b*a.len == b.a {
		return makeView(a.l, a.a, a.b, a.len+b.len)
	}
	n := alloc()
	n.typ = typConcat
	n.len = a.len + b.len
	n.a = 0
	n.b = 0
	n.l = a
	n.r = b
	return n
}

func min64(a, b int64) int64 {
	if a < b {
		return a
	}
	return b
}

type Task struct {
	node *Node
	a    int64
	d    int64
	m    int64
}

func materialize(root *Node, src []byte) []byte {
	out := make([]byte, int(root.len))
	idx := 0
	stack := make([]Task, 0, 1024)
	n := root
	var a, d, m int64 = 1, 1, root.len
	for {
		for {
			if n == nil || m <= 0 {
				break
			}
			switch n.typ {
			case typView:
				a = n.a + n.b*(a-1)
				if m == 1 {
					d = 1
				} else {
					d = n.b * d
				}
				n = n.l
			case typConcat:
				lenL := n.l.len
				if a > lenL {
					a -= lenL
					n = n.r
					continue
				}
				t := (lenL-a)/d + 1
				if t >= m {
					n = n.l
					continue
				}
				stack = append(stack, Task{node: n.r, a: a + d*t - lenL, d: d, m: m - t})
				m = t
				n = n.l
			default:
				start := n.a + n.b*(a-1)
				if m == 1 {
					out[idx] = src[int(start-1)]
					idx++
				} else {
					step := n.b * d
					if step == 1 {
						s := int(start - 1)
						e := s + int(m)
						copy(out[idx:idx+int(m)], src[s:e])
						idx += int(m)
					} else {
						pos := start - 1
						for i := int64(0); i < m; i++ {
							out[idx] = src[int(pos)]
							idx++
							pos += step
						}
					}
				}
				break
			}
			if n == nil || n.typ == typOrig {
				break
			}
		}
		if len(stack) == 0 {
			break
		}
		t := stack[len(stack)-1]
		stack = stack[:len(stack)-1]
		n = t.node
		a = t.a
		d = t.d
		m = t.m
	}
	return out
}

func main() {
	data, _ := io.ReadAll(os.Stdin)
	f := Fast{data: data, n: len(data)}
	src := append([]byte(nil), f.nextBytes()...)
	k := f.nextInt64()
	nm := int(f.nextInt64())
	pool = make([]Node, 30*nm+100)
	curLen := int64(len(src))
	root := makeOrig(1, 1, min64(curLen, k))
	for i := 0; i < nm; i++ {
		l := f.nextInt64()
		r := f.nextInt64()
		m := r - l + 1
		curLen += m
		newLen := min64(curLen, k)
		if r >= newLen {
			root = makeView(root, 1, 1, newLen)
			continue
		}
		a := makeView(root, 1, 1, r)
		b := makeView(root, l, 1, m)
		copyLen := min64(m, newLen-r)
		evenCnt := m / 2
		var d *Node
		if copyLen <= evenCnt {
			d = makeView(b, 2, 2, copyLen)
		} else {
			d = makeConcat(makeView(b, 2, 2, evenCnt), makeView(b, 1, 2, copyLen-evenCnt))
		}
		tailLen := newLen - r - copyLen
		e := makeView(root, r+1, 1, tailLen)
		root = makeConcat(makeConcat(a, d), e)
	}
	out := materialize(root, src)
	w := bufio.NewWriterSize(os.Stdout, 1<<22)
	w.Write(out)
	w.WriteByte('\n')
	w.Flush()
}