Language: C++

package main

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

// -----------------------------------------------------------------------------

// IO helper functions

// Returns next token from input.  It must be initialized by SetInput()
// before the first call.
var nextToken func() ([]byte, error)
var nextLine func() ([]byte, error)

// Holds a buffer for output.  It must be initialized by SetOutput().
// All IO fucntions (read*() and [e]print*()) should write to OutputWriter
// instead of this.
var OutputBuffer *bufio.Writer

// Holds an io.Writer.  It must be initialized by SetOutput()
var OutputWriter io.Writer

// Set IO functions for interactive input/output.
func SetInteractive(w io.Writer, r io.Reader) {
	SetUnbefferedInput(r)
	OutputBuffer = nil
	OutputWriter = w
}

// Setup OutputBuffer and OutputWriter.
func SetOutput(w io.Writer) {
	OutputBuffer = bufio.NewWriter(w)
	OutputWriter = OutputBuffer
}

// Flushes OutputBuffer
func Flush() {
	if OutputBuffer != nil {
		OutputBuffer.Flush()
	}
}

// Returns true if c is a white space
func IsSpace(c byte) bool {
	switch c {
	case '\t', '\n', '\v', '\f', '\r', ' ':
		return true
	}
	return false
}

func IsNewLine(c byte) bool {
	switch c {
	case '\n', '\r':
		return true
	}
	return false
}

// Setup nextToken with input buffer.
func SetInput(r io.Reader) {
	buf := new(bytes.Buffer)
	var b []byte

	var i int
	rest := func() ([]byte, error) {
		for i < len(b) && IsSpace(b[i]) {
			i++
		}
		if i == len(b) {
			return nil, io.ErrUnexpectedEOF
		}
		j := i
		for i < len(b) && !IsSpace(b[i]) {
			i++
		}
		return b[j:i], nil
	}
	initial := func() ([]byte, error) {
		io.Copy(buf, r)
		b = buf.Bytes()
		nextToken = rest
		return rest()
	}
	nextToken = initial

	restLn := func() ([]byte, error) {
		for i < len(b) && IsNewLine(b[i]) {
			i++
		}
		if i == len(b) {
			return nil, io.ErrUnexpectedEOF
		}
		j := i
		for i < len(b) && !IsNewLine(b[i]) {
			i++
		}
		return b[j:i], nil
	}

	initialLn := func() ([]byte, error) {
		io.Copy(buf, r)
		b = buf.Bytes()
		nextLine = restLn
		return restLn()
	}
	nextLine = initialLn
}

// Setup nextToken without input buffer.
func SetUnbefferedInput(r io.Reader) {
	buf := bufio.NewReader(r)
	var b []byte

	var i int
	nextToken = func() ([]byte, error) {
		var err error
		if i == len(b) {
			b, err = buf.ReadBytes('\n')
			if err != nil {
				return nil, err
			}
			i = 0
			j := len(b) - 1
			for 0 <= j && IsSpace(b[j]) {
				j--
			}
			b = b[0 : j+1]
		}
		for i < len(b) && IsSpace(b[i]) {
			i++
		}
		j := i
		for i < len(b) && !IsSpace(b[i]) {
			i++
		}
		if i == j {
			return nil, io.ErrUnexpectedEOF
		}
		return b[j:i], nil
	}
}

// -----------------------------------------------------------------------------

// IO functions

// Reads next token and return it as []byte
func readb() []byte {
	b, err := nextToken()
	if err != nil {
		panic(err)
	}
	return b
}

// Reads next token and return it as string
func reads() string {
	return string(readb())
}

// Read next line as []byte
func readbln() []byte {
	b, err := nextLine()
	if err != nil {
		panic(err)
	}
	return b
}

// Read next line as string
func readsln() string {
	return string(readbln())
}

// Reads next token and return it as int64
func readll() int64 {
	i, err := strconv.ParseInt(reads(), 10, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

// Reads next token and return it as int
func readi() int {
	return int(readll())
}

// Reads next token and return it as float64
func readf() float64 {
	f, err := strconv.ParseFloat(reads(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

// Write args to OutputWriter with the format f
func printf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(OutputWriter, f, args...)
}

// Write args to OutputWriter without format
func println(args ...interface{}) (int, error) {
	return fmt.Fprintln(OutputWriter, args...)
}

// Write args to stderr with the format f
func eprintf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(os.Stderr, f, args...)
}

// Write args to stderr without format
func eprintln(args ...interface{}) (int, error) {
	return fmt.Fprintln(os.Stderr, args...)
}

// -----------------------------------------------------------------------------

// Simple math functions

const (
	// big prime
	INF  = 1000000007
	INF2 = 1000000009
	INF3 = 998244353
)

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

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

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

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

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func absll(a int64) int64 {
	if a < 0 {
		return -a
	}
	return a
}

// egcd(a, b) returns d, x, y:
//   d is gcd(a,b)
//   x, y are  integers that satisfy ax + by = d
func egcd(a, b int) (int, int, int) {
	if b == 0 {
		return a, 1, 0
	}
	d, x, y := egcd(b, a%b)
	return d, y, x - a/b*y
}

func egcdll(a, b int64) (int64, int64, int64) {
	if b == 0 {
		return a, 1, 0
	}
	d, x, y := egcdll(b, a%b)
	return d, y, x - a/b*y
}

func gcd(a, b int) int {
	d, _, _ := egcd(a, b)
	return d
}

func gcdll(a, b int64) int64 {
	d, _, _ := egcdll(a, b)
	return d
}

// set up IO functions
func init() {
	// for non-interactive
	SetInput(os.Stdin)
	SetOutput(os.Stdout)

	// Enable below when interactive.  Its ok to leave above intact.
	// SetInteractive(os.Stdout, os.Stdin)
}

func main() {
	defer Flush()

	a := readi()
	b := readi()
	x := readi()

	a1 := (a - 1) / x
	b1 := b / x
	println(b1 - a1)
}


Compiler output:
a.cc:1:1: error: 'package' does not name a type
    1 | package main
      | ^~~~~~~
a.cc:37:1: error: 'func' does not name a type
   37 | func SetOutput(w io.Writer) {
      | ^~~~
a.cc:43:1: error: 'func' does not name a type
   43 | func Flush() {
      | ^~~~
a.cc:50:1: error: 'func' does not name a type
   50 | func IsSpace(c byte) bool {
      | ^~~~
a.cc:58:1: error: 'func' does not name a type
   58 | func IsNewLine(c byte) bool {
      | ^~~~
a.cc:67:1: error: 'func' does not name a type
   67 | func SetInput(r io.Reader) {
      | ^~~~
a.cc:117:1: error: 'func' does not name a type
  117 | func SetUnbefferedInput(r io.Reader) {
      | ^~~~
a.cc:155:1: error: 'func' does not name a type
  155 | func readb() []byte {
      | ^~~~
a.cc:164:1: error: 'func' does not name a type
  164 | func reads() string {
      | ^~~~
a.cc:169:1: error: 'func' does not name a type
  169 | func readbln() []byte {
      | ^~~~
a.cc:178:1: error: 'func' does not name a type
  178 | func readsln() string {
      | ^~~~
a.cc:183:1: error: 'func' does not name a type
  183 | func readll() int64 {
      | ^~~~
a.cc:192:1: error: 'func' does not name a type
  192 | func readi() int {
      | ^~~~
a.cc:197:1: error: 'func' does not name a type
  197 | func readf() float64 {
      | ^~~~
a.cc:206:1: error: 'func' does not name a type
  206 | func printf(f string, args ...interface{}) (int, error) {
      | ^~~~
a.cc:206:42: error: expected unqualified-id before ')' token
  206 | func printf(f string, args ...interface{}) (int, error) {
      |                                          ^
a.cc:211:1: error: 'func' does not name a type
  211 | func println(args ...interface{}) (int, error) {
      | ^~~~
a.cc:211:33: error: expected unqualified-id before ')' token
  211 | func println(args ...interface{}) (int, error) {
      |                                 ^
a.cc:216:1: error: 'func' does not name a type
  216 | func eprintf(f string, args ...interface{}) (int, error) {
      | ^~~~
a.cc:216:43: error: expected unqualified-id before ')' token
  216 | func eprintf(f string, args ...interface{}) (int, error) {
      |                                           ^
a.cc:221:1: error: 'func' does not name a type
  221 | func eprintln(args ...interface{}) (int, error) {
      | ^~~~
a.cc:221:34: error: expected unqualified-id before ')' token
  221 | func eprintln(args ...interface{}) (int, error) {
      |                                  ^
a.cc:231:12: error: expected ')' before '=' token
  231 |         INF  = 1000000007
      |            ^ ~
      |            )
a.cc:229:7: note: to match this '('
  229 | const (
      |       ^
a.cc:243:1: error: 'func' does not name a type
  243 | func minll(a, b int64) int64 {
      | ^~~~
a.cc:250:1: error: 'func' does not name a type
  250 | func max(a, b int) int {
      | ^~~~
a.cc:257:1: error: 'func' does not name a type
  257 | func maxll(a, b int64) int64 {
      | ^~~~
a.cc:264:1: error: 'func' does not name a type
  264 | func abs(a int) int {
      | ^~~~
a.cc:271:1: error: 'func' does not name a type
  271 | func absll(a int64) int64 {
      | ^~~~
a.cc:281:1: error: 'func' does not name a type
  281 | func egcd(a, b int) (int, int, int) {
      | ^~~~
a.cc:289:1: error: 'func' does not name a type
  289 | func egcdll(a, b int64) (int64, int64, int64) {
      | ^~~~
a.cc:297:1: error: 'func' does not name a type
  297 | func gcd(a, b int) int {
      | ^~~~
a.cc:302:1: error: 'func' does not name a type
  302 | func gcdll(a, b int64) int64 {
      | ^~~~
a.cc:308:1: error: 'func' does not name a type
  308 | func init() {
      | ^~~~
a.cc:317:1: error: 'func' does not name a type
  317 | func main() {
      | ^~~~