List of top Computer Science & Information Technology Questions asked in OJEE

Consider the grammar $S \rightarrow aSa \mid bSb \mid a \mid b$. Which one of the following options correctly characterizes the language generated by the given grammar over the alphabet {a,b} 
 

What is the value of the postfix expression: $6\ 12\ 2\ 4\ +\ /\ *\ ?$
Consider the following C function foo(int n). How many times does foo(2) get called on making the call foo(5)?
C Function: 
float foo(int n){
    if(n <= 2) return 1;
    else return (2*foo(n-1) + 3*foo(n-2));
}
System calls are usually invoked by using which one of the following means?
Which one of the following is not necessarily saved on a context switch between two processes?
Von Neumann computers belong to which one of the following classes of computers?
Which one of the following derivations does a top-down parser use while parsing an input string? The input is assumed to be scanned from left to right.
To prove that a problem $\chi$ in NP is NP-complete, it would be sufficient to show which one of the following to be true?
In a compiler, type checking is normally done during which phase?
Which one of the following classes of statements usually produces no executable code when compiled?
Suppose you are given pointers to the first and the last nodes of a singly linked list, which one of the following operations would require traversal of the linked list?
Which one of the following is an important advantage of the DMA mode of data transfer over programmed data transfer?
Which one of the following problems is undecidable?
The output of a lexical analyzer is which one of the following?
Suppose in a time-shared operating system, a certain process is performing I/O. It must be in which one of the following states?
What is the time complexity of the Bellman-Ford single-source shortest path algorithm on a completely connected weighted graph of $n$ vertices?
Consider a processor that generates 32-bit virtual addresses. It uses a direct mapped cache whose size is 32 KByte and has 32 Byte blocks. What is the number of bits needed for cache addressing?
What is the amount of ROM needed to implement a 4-bit multiplier?
How many null links does an arbitrary binary tree with $n$ nodes have?
Which one of the following recurrence relations best represents the time complexity of the binary search algorithm running on an ordered array of $n$ elements?