✅ Operating System collection of software that manages computer hardware resources and provides common services for computer programs > communication channel between system hardware and sys...

these methods are for dividing the main memory to run multi programming two techniques for organizing, allocating memory ✅ Memory Continuous memory Incontinuous memory ✅ Paging ...

kernel resources that provide synchronization services synchronization services to prevent multi threads to access shared resrouce at the same time limit access to shared resource in multi pro...

✅ Race Condition when several processes need shared resource at the same time, can affect the result value when accessed at concurrent time, data integrity ⬇️ several process attempt sha...

✅ Trie = Prefix Tree TRIEval: finding something or obtaining it tree-like data structure efficient storing, retrieval of key-value pairs prefix-based searching trie is String searching ...

✅ Hash key ➕ value for the efficient management of data, mapping data of arbitary length to fixed-length generate fixed-size output of an input of variable size using hash functions ...

✅ Binary Search Tree binary search ➕ linked list 👍🏻 searching data binary search: search time complexity: O(longN) 👍🏻 insertion, deletion time complexity: impossibl...

✅ Tree node ➕ edges a tree cannot have cycles(if there is cycle, then it is a graph) one unique way from root to a certain node if count of node is n, number of edges will be n-1 👍🏻 ...

✅ Priority Queue each data has priority. the data with priority will dequeue first. elements are retrieved based on their priority ✅ Heap made for priority queue complete binary tree dat...

✅ Stack input, output same direction LIFO 💡 usage DFS 문자열 역순 연산자 후위표기법 💡 methods push pop isEmpty isFull: requires MAX_SIZE ✅ Queue input, output different directi...