For problem statement at 0-999/500-599/550-559/554/problemA.txt this is a correct solution, but verifier at 0-999/500-599/550-559/554/verifierA.go ends with All 100 tests passed can you fix the verifier? package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

func main() {
	in := bufio.NewReader(os.Stdin)
	out := bufio.NewWriter(os.Stdout)
	defer out.Flush()

	var s string
	fmt.Fscan(in, &s)

	res := make(map[string]struct{})
	for i := 0; i <= len(s); i++ {
		for c := 'a'; c <= 'z'; c++ {
			var b strings.Builder
			b.Grow(len(s) + 1)
			b.WriteString(s[:i])
			b.WriteByte(byte(c))
			b.WriteString(s[i:])
			res[b.String()] = struct{}{}
		}
	}
	fmt.Fprintln(out, len(res))
}