What do you mean by external sorting?
Can hashmap have same key?
What is heap and its types?
Should I use hashmap or hashtable?
Which is faster quick sort or merge sort?
What is an array vs list?
what is Singly Linked list?
Which sorting has less time complexity?
what are the applications that use Linked lists?
Can we define the size of arraylist?
What is nsmutablearray?
Which collection is fail safe?
What method removes the value from the top of a stack?