leetcode@ [146] LRU Cache (TREEMAP)

https://leetcode.com/problems/lru-cache/

Design and implement a data structure for Least recently Used (LRU) cache. It should support the following operations: get and set .

get(key)-Get The value ('ll always be positive) of the key if the key exists in the cache, otherwise return-1.
set(key, value)-Set or insert the value if the key is not already present. When the cache is reached its capacity, it should invalidate the least recently used item before inserting a new item.

classPair { Public intkey;  Public intvalue;  PublicPairintKintv) {Super();  This. Key =K;  This. Value =v; }         Public voidSetValue (intvalue) {         This. Value =value; }    }classCmpImplementsComparator { Public intCompare (Object O1, Object O2) {pair P1=(pair) O1; Pair P2=(pair) O2; if(P1.key <p2.key) {return-1; } Else if(P1.key = =p2.key) {if(P1.value = =p2.value) {return0; } Else if(P1.value <p2.value) {return-1; } Else {                return1; }        } Else {            return1; }    }} Public classLRUCache { Publicset<pair> stack =NULL;  PublicHashmap<integer, integer> mapping =NULL;  PublicTreemap<integer, integer> Timetokey =NULL;  PublicTreemap<integer, integer> keytotime =NULL;  Public intCap = 0;  Public intCounter = 0;  PublicLRUCache (intcapacity) {         This. mapping =NewHashmap<integer, integer> ();  This. Timetokey =NewTreemap<integer, integer> ();  This. Keytotime =NewTreemap<integer, integer> ();  This. Cap =capacity;  This. Counter = 0; }         Public intGetintkey) {                if(!Mapping.containskey (Key)) {            return-1; } Else{counter++; intValue =Mapping.get (key); intTime =Keytotime.get (key);                        Keytotime.put (key, counter);            Timetokey.remove (time);                        Timetokey.put (counter, key); returnvalue; }    }         Public voidSetintKeyintvalue) {Counter++; if(Mapping.containskey (key)) {intTime =Keytotime.get (key);                        Keytotime.put (key, counter);            Timetokey.remove (time);                        Timetokey.put (counter, key);                    Mapping.put (key, value); } Else {                        if(Mapping.size () <cap)                {Mapping.put (key, value);                Keytotime.put (key, counter);                            Timetokey.put (counter, key); } Else {                                intLRU =timetokey.pollfirstentry (). GetValue ();                Mapping.remove (LRU);                                Mapping.put (key, value);                Keytotime.put (key, counter);            Timetokey.put (counter, key); }        }    }}

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[email protected] [146] LRU Cache (TREEMAP)