For problem statement at 0-999/600-699/660-669/666/problemC.txt this is a correct solution, but verifier at 0-999/600-699/660-669/666/verifierC.go ends with All tests passed can you fix the verifier? ```go
package main

import (
	"bufio"
	"os"
	"strconv"
)

const MOD int64 = 1000000007

var fact [100005]int64
var invFact [100005]int64
var pow25 [100005]int64
var pow26 [100005]int64

func init() {
	fact[0] = 1
	invFact[0] = 1
	pow25[0] = 1
	pow26[0] = 1
	for i := 1; i <= 100000; i++ {
		fact[i] = (fact[i-1] * int64(i)) % MOD
		pow25[i] = (pow25[i-1] * 25) % MOD
		pow26[i] = (pow26[i-1] * 26) % MOD
	}
	invFact[100000] = power(fact[100000], MOD-2)
	for i := 99999; i >= 1; i-- {
		invFact[i] = (invFact[i+1] * int64(i+1)) % MOD
	}
}

func power(base, exp int64) int64 {
	res := int64(1)
	base %= MOD
	for exp > 0 {
		if exp%2 == 1 {
			res = (res * base) % MOD
		}
		base = (base * base) % MOD
		exp /= 2
	}
	return res
}

func nCr(n, r int) int64 {
	if r < 0 || r > n {
		return 0
	}
	return fact[n] * invFact[r] % MOD * invFact[n-r] % MOD
}

type Query struct {
	id int
	n  int
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]byte, 1024*1024), 1024*1024*10)
	scanner.Split(bufio.ScanWords)

	if !scanner.Scan() {
		return
	}
	m, _ := strconv.Atoi(scanner.Text())

	scanner.Scan()
	s := scanner.Text()
	k := len(s)

	queriesByK := make(map[int][]Query)
	var queryCount int

	for i := 0; i < m; i++ {
		scanner.Scan()
		t, _ := strconv.Atoi(scanner.Text())
		if t == 1 {
			scanner.Scan()
			s = scanner.Text()
			k = len(s)
		} else {
			scanner.Scan()
			n, _ := strconv.Atoi(scanner.Text())
			queriesByK[k] = append(queriesByK[k], Query{id: queryCount, n: n})
			queryCount++
		}
	}

	ans := make([]int64, queryCount)
	var k_ans [100005]int64

	for kVal, queries := range queriesByK {
		maxN := 0
		for _, q := range queries {
			if q.n > maxN {
				maxN = q.n
			}
		}

		if maxN >= kVal {
			S := (pow26[kVal] - 1 + MOD) % MOD
			k_ans[kVal] = 1
			for n := kVal; n < maxN; n++ {
				term := (nCr(n, kVal-1) * pow25[n-kVal+1]) % MOD
				S = (26*S - term) % MOD
				if S < 0 {
					S += MOD
				}
				k_ans[n+1] = (pow26[n+1] - S + MOD) % MOD
			}
		}

		for _, q := range queries {
			if q.n >= kVal {
				ans[q.id] = k_ans[q.n]
			} else {
				ans[q.id] = 0
			}
		}
	}

	out := bufio.NewWriter(os.Stdout)
	for i := 0; i < queryCount; i++ {
		out.WriteString(strconv.FormatInt(ans[i], 10) + "\n")
	}
	out.Flush()
}
```