For problem statement at 2000-2999/2000-2099/2040-2049/2046/problemE1.txt this is a correct solution, but verifier at 2000-2999/2000-2099/2040-2049/2046/verifierE1.go ends with All 18 tests passed. can you fix the verifier? package main

import (
	"bytes"
	"io"
	"os"
)

type Part struct {
	a int
	b int
	s int
}

var data []byte
var ptr int

func nextInt() int {
	for ptr < len(data) && (data[ptr] < '0' || data[ptr] > '9') {
		ptr++
	}
	x := 0
	for ptr < len(data) && data[ptr] >= '0' && data[ptr] <= '9' {
		x = x*10 + int(data[ptr]-'0')
		ptr++
	}
	return x
}

func writeInt(out *bytes.Buffer, x int) {
	if x == 0 {
		out.WriteByte('0')
		return
	}
	var buf [20]byte
	n := 0
	for x > 0 {
		buf[n] = byte('0' + x%10)
		x /= 10
		n++
	}
	for i := n - 1; i >= 0; i-- {
		out.WriteByte(buf[i])
	}
}

func main() {
	data, _ = io.ReadAll(os.Stdin)
	t := nextInt()
	var out bytes.Buffer

	for ; t > 0; t-- {
		n := nextInt()
		m := nextInt()

		parts := make([]Part, n+1)
		used := make(map[int]struct{}, n+4)

		for i := 1; i <= n; i++ {
			a := nextInt()
			b := nextInt()
			s := nextInt()
			parts[i] = Part{a: a, b: b, s: s}
			used[s] = struct{}{}
		}

		var city1, city2 []int
		for c := 0; c < m; c++ {
			k := nextInt()
			if c == 0 {
				city1 = make([]int, k)
				for i := 0; i < k; i++ {
					city1[i] = nextInt()
				}
			} else if c == 1 {
				city2 = make([]int, k)
				for i := 0; i < k; i++ {
					city2[i] = nextInt()
				}
			} else {
				for i := 0; i < k; i++ {
					nextInt()
				}
			}
		}

		A := parts[city1[0]].a
		for _, id := range city1[1:] {
			if parts[id].a < A {
				A = parts[id].a
			}
		}

		B := parts[city2[0]].a
		for _, id := range city2[1:] {
			if parts[id].a > B {
				B = parts[id].a
			}
		}

		if A > B {
			dummy := 1000000000
			for {
				if _, ok := used[dummy]; !ok {
					break
				}
				dummy--
			}
			writeInt(&out, 1)
			out.WriteByte('\n')
			writeInt(&out, A)
			out.WriteByte(' ')
			writeInt(&out, dummy)
			out.WriteByte('\n')
			continue
		}

		block := make(map[int]int)
		for _, id := range city2 {
			p := parts[id]
			if p.a >= A {
				if v, ok := block[p.s]; !ok || p.b > v {
					block[p.s] = p.b
				}
			}
		}

		specNeed := make(map[int]int)
		ok := true
		hasStrong := false

		for _, id := range city1 {
			p := parts[id]
			if p.a > B {
				hasStrong = true
				continue
			}
			limit := B
			if v, exists := block[p.s]; exists && v > limit {
				limit = v
			}
			if p.b <= limit {
				ok = false
				break
			}
			specNeed[p.s] = limit + 1
		}

		if !ok {
			out.WriteByte('-')
			out.WriteByte('1')
			out.WriteByte('\n')
			continue
		}

		needDummies := 1
		if hasStrong {
			needDummies = 2
		}
		dummies := make([]int, 0, needDummies)
		cand := 1000000000
		for len(dummies) < needDummies {
			if _, exists := used[cand]; !exists {
				dummies = append(dummies, cand)
				used[cand] = struct{}{}
			}
			cand--
		}

		total := 1 + len(specNeed)
		if hasStrong {
			total++
		}

		writeInt(&out, total)
		out.WriteByte('\n')

		writeInt(&out, A)
		out.WriteByte(' ')
		writeInt(&out, dummies[0])
		out.WriteByte('\n')

		if hasStrong {
			writeInt(&out, B+1)
			out.WriteByte(' ')
			writeInt(&out, dummies[1])
			out.WriteByte('\n')
		}

		for s, d := range specNeed {
			writeInt(&out, d)
			out.WriteByte(' ')
			writeInt(&out, s)
			out.WriteByte('\n')
		}
	}

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