Problem:
Score : 200 points

Problem Statement

A string is called a KEYENCE string when it can be changed to keyence by removing its contiguous substring (possibly empty) only once.

Given a string S consisting of lowercase English letters, determine if S is a KEYENCE string.

Constraints

The length of S is between 7 and 100 (inclusive).

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If S is a KEYENCE string, print YES; otherwise, print NO.

Sample Input 1

keyofscience

Sample Output 1

YES

keyence is an abbreviation of key of science.

Sample Input 2

mpyszsbznf

Sample Output 2

NO

Sample Input 3

ashlfyha

Sample Output 3

NO

Sample Input 4

keyence

Sample Output 4

YES

Solution in Go (1.14.1) (judge verdict: Wrong Answer)

package main

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

var sc = bufio.NewScanner(os.Stdin)

func main() {
	scanInit()
	key := "keyence"
	s := nextStr()

	for i := 0; i < len(key); i++ {
		now1st := key[:i+1]
		now2nd := key[i+1:]

		idx1 := strings.Index(s, now1st)
		idx2 := strings.Index(s, now2nd)
		if idx1 == -1 || idx2 == -1 {
			continue
		}
		if idx1 >= idx2 {
			continue
		}
		fmt.Println("YES")
		return
	}

	fmt.Println("NO")
	return
}

// ---- readfunc
func scanInit() {
	const cap = 200 * 1024 // default=64*1024
	var buf = make([]byte, cap)
	sc.Buffer(buf, cap)
	sc.Split(bufio.ScanWords)
	return
}
func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}
func nextStr() string {
	sc.Scan()
	return sc.Text()
}