Problem:
Score : 100 points

Problem Statement

On some day in January 2018, Takaki is writing a document. The document has a column where the current date is written in yyyy/mm/dd format. For example, January 23, 2018 should be written as 2018/01/23.

After finishing the document, she noticed that she had mistakenly wrote 2017 at the beginning of the date column. Write a program that, when the string that Takaki wrote in the date column, S, is given as input, modifies the first four characters in S to 2018 and prints it.

Constraints

S is a string of length 10.

The first eight characters in S are 2017/01/.

The last two characters in S are digits and represent an integer between 1 and 31 (inclusive).

Input

Input is given from Standard Input in the following format:

S

Output

Replace the first four characters in S with 2018 and print it.

Sample Input 1

2017/01/07

Sample Output 1

2018/01/07

Sample Input 2

2017/01/31

Sample Output 2

2018/01/31

Solution in Go (1.6) (judge verdict: Accepted)

package main

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

func main() {
	fsc := NewFastScanner()
	S := fsc.Next()
	fmt.Println("2018" + S[4:])
}

//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) NextIntArray() []int {
	s.pre()
	start := s.p
	result := []int{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 0)
			result = append(result, int(v))
			start = s.p + 1
		}
	}

	return result
}

func (s *FastScanner) NextInt64Array() []int64 {
	s.pre()
	start := s.p
	result := []int64{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 64)
			result = append(result, v)
			start = s.p + 1
		}
	}
	return result
}

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
		}
	}
}

//Max,Min
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
}

//Gcd
func IntGcd(a, b int) int {
	if a < b {
		b, a = a, b
	}
	if b == 0 {
		return a
	}
	return IntGcd(b, a%b)
}
func Int64Gcd(a, b int64) int64 {
	if a < b {
		b, a = a, b
	}
	if b == 0 {
		return a
	}
	return Int64Gcd(b, a%b)
}

func IntAbs(a int) int {
	if a < 0 {
		a *= -1
	}
	return a
}

func Int64Abs(a int64) int64 {
	if a < 0 {
		a *= -1
	}
	return a
}