import java.util.Random;

class SkipListNode $\{$

int value;

SkipListNode$[]$ next;

public SkipListNode$($int value, int level$)\{$

this.value $=$ value;

this.next $=$ new SkipListNode$[$level $+1]$;

$\}$

$\}$

public class SkipList $\{$

private static final int MAX$\_$LEVEL $=4$;

private int level;

private final SkipListNode head;

private final Random rand;

public SkipList$()\{$

this.level $=0$;

this.head $=$ new SkipListNode$($Integer$.$MIN$\_$VALUE, MAX$\_$LEVEL$)$;

this.rand $=$ new Random$()$;

$\}$

public void insert$($int value$)\{$

int newLevel $=$ randomLevel$()$;

SkipListNode newNode $=$ new SkipListNode$($value$,$ newLevel$)$;

SkipListNode$[]$ update $=$ new SkipListNode$[$MAX$\_$LEVEL $+1]$;

SkipListNode current $=$ head;

for $($int i $=$ level; i $>=0$; i$--)\{$

while $($current$.$next$[$i$]!=$ null && current.next$[$i$].$value $<$ value$)\{$

current $=$ current.next$[$i$]$;

$\}$

update$[$i$]=$ current;

$\}$

for $($int i $=0$; i $<=$ newLevel; i$++)\{$

newNode.next$[$i$]=$ update$[$i$].$next$[$i$]$;

update$[$i$].$next$[$i$]=$ newNode;

$\}$

if $($newLevel $>$ level$)\{$

level $=$ newLevel;

$\}$

$\}$

public boolean search$($int value$)\{$

SkipListNode current $=$ head;

for $($int i $=$ level; i $>=0$; i$--)\{$

while $($current$.$next$[$i$]!=$ null && current.next$[$i$].$value $<$ value$)\{$

current $=$ current.next$[$i$]$;

$\}$

$\}$

current $=$ current.next$[0]$;

return current $!=$ null && current.value $==$ value;

$\}$

private int randomLevel$()\{$

int randomLevel $=0$;

while $($Math$.$random$()<0\mathrm{.}5$ && randomLevel $<$ MAX$\_$LEVEL$)\{$

randomLevel$++$;

$\}$

return randomLevel;

$\}$

public static void main$($String$[]$ args$)\{$

SkipList skipList $=$ new SkipList$()$;

int$[]$ values $=\{7,11,15,22,25,30,42,53\}$;

for $($int value : values$)\{$

skipList.insert$($value$)$;

$\}$

System.out.println$("$Arama sonu$$lar$$:$")$;

for $($int value : values$)\{$

System.out.println$($value $+"$ bulundu mu$?"+$ skipList.search$($value$))$;

$\}$

$\}$

$\}$ BU KODDA private final Random rand; KISMINDA VAR$$ABLE RAND $$S NEVER EEAD HATASI ALIYORUM VE BU YUZDEN KODUM $$ALI$$MIYOR$.$ NE YAPMAM GEREK