Language: C++

package main

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

func main() {
	fsc := NewFastScanner()
	S := fsc.Next()
	check := map[rune]int{}
	for _, c := range S {
		check[c]++
	}
	ok := true
	for _, v := range S {
		if v > 1 {
			ok = false
		}
	}
	if ok {
		fmt.Println("yes")
	} else {
		fmt.Println("no")
	}
}

//template
type FastScanner struct {
	r   *bufio.Reader
	buf []byte
	p   int
}

func NewFastScanner() *FastScanner {
	rdr := bufio.NewReaderSize(os.Stdin, 1024)
	return &FastScanner{r: rdr}
}
func (s *FastScanner) Next() string {
	s.pre()
	start := s.p
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			break
		}
	}
	result := string(s.buf[start:s.p])
	s.p++
	return result
}
func (s *FastScanner) NextLine() string {
	s.pre()
	start := s.p
	s.p = len(s.buf)
	return string(s.buf[start:])
}
func (s *FastScanner) NextInt() int {
	v, _ := strconv.Atoi(s.Next())
	return v
}
func (s *FastScanner) NextInt64() int64 {
	v, _ := strconv.ParseInt(s.Next(), 10, 64)
	return v
}

func (s *FastScanner) pre() {
	if s.p >= len(s.buf) {
		s.readLine()
		s.p = 0
	}
}
func (s *FastScanner) readLine() {
	s.buf = make([]byte, 0)
	for {
		l, p, e := s.r.ReadLine()
		if e != nil {
			panic(e)
		}
		s.buf = append(s.buf, l...)
		if !p {
			break
		}
	}
}

func IntMax(a, b int) int {
	if a < b {
		return b
	}
	return a
}

func Int64Max(a, b int64) int64 {
	if a < b {
		return b
	}
	return a
}
func Float64Max(a, b float64) float64 {
	if a < b {
		return b
	}
	return a
}

func IntMin(a, b int) int {
	if a > b {
		return b
	}
	return a
}

func Int64Min(a, b int64) int64 {
	if a > b {
		return b
	}
	return a
}
func Float64Min(a, b float64) float64 {
	if a > b {
		return b
	}
	return a
}


Compiler output:
a.cc:1:1: error: 'package' does not name a type
    1 | package main
      | ^~~~~~~
a.cc:31:1: error: 'type' does not name a type; did you mean 'typeof'?
   31 | type FastScanner struct {
      | ^~~~
      | typeof
a.cc:37:1: error: 'func' does not name a type
   37 | func NewFastScanner() *FastScanner {
      | ^~~~
a.cc:41:6: error: expected constructor, destructor, or type conversion before '(' token
   41 | func (s *FastScanner) Next() string {
      |      ^
a.cc:53:6: error: expected constructor, destructor, or type conversion before '(' token
   53 | func (s *FastScanner) NextLine() string {
      |      ^
a.cc:59:6: error: expected constructor, destructor, or type conversion before '(' token
   59 | func (s *FastScanner) NextInt() int {
      |      ^
a.cc:63:6: error: expected constructor, destructor, or type conversion before '(' token
   63 | func (s *FastScanner) NextInt64() int64 {
      |      ^
a.cc:68:6: error: expected constructor, destructor, or type conversion before '(' token
   68 | func (s *FastScanner) pre() {
      |      ^
a.cc:74:6: error: expected constructor, destructor, or type conversion before '(' token
   74 | func (s *FastScanner) readLine() {
      |      ^
a.cc:88:1: error: 'func' does not name a type
   88 | func IntMax(a, b int) int {
      | ^~~~
a.cc:95:1: error: 'func' does not name a type
   95 | func Int64Max(a, b int64) int64 {
      | ^~~~
a.cc:101:1: error: 'func' does not name a type
  101 | func Float64Max(a, b float64) float64 {
      | ^~~~
a.cc:108:1: error: 'func' does not name a type
  108 | func IntMin(a, b int) int {
      | ^~~~
a.cc:115:1: error: 'func' does not name a type
  115 | func Int64Min(a, b int64) int64 {
      | ^~~~
a.cc:121:1: error: 'func' does not name a type
  121 | func Float64Min(a, b float64) float64 {
      | ^~~~