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GATE CS question library

Practise GATE CS Computer Science previous year questions free. Browse by subject, syllabus topic, year and question type, with answers and available solutions.

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20 on this page
Official PYQ2015General AptitudeMCQ · 1 mark
Which one of the following combinations is incorrect?
Official PYQ2015General AptitudeMCQ · 1 mark
Based on the given statements, select the most appropriate option to solve the given question. If two floors in a certain building are 99 feet apart, how many steps are there in a set of stairs that extends from the first floor to the second floor of the building? Statements: Each step is 3/43/4 foot high. Each step is 11 foot wide.
Official PYQ2015General AptitudeMCQ · 1 mark
Given Set A=2,3,4,5A= {2, 3, 4, 5} and Set B=11,12,13,14,15B= { 11, 12, 13, 14, 15}, two numbers are randomly selected, one from each set. What is the probability that the sum of the two numbers equals 1616?
Official PYQ2015General AptitudeMCQ · 1 mark
Which of the following options is the closest in meaning of the sentence below? She enjoyed herself immensely at the party.
Official PYQ2015General AptitudeMCQ · 1 mark
Didn't you buy ____ when you went shopping?
Official PYQ2015Engineering MathematicsPropositional and First Order LogicMCQ · 1 mark
Which one of the following well-formed formulae is a tautology?
Official PYQ2015Engineering MathematicsSets, Relations and FunctionsNAT · 1 mark
Let XX and YY denote the sets containing 22 and 2020 distinct objects respectively and FF denote the set of all possible functions defined from XX to YY. Let ff be randomly chosen from FF. The probability of ff being one-to-one is ______.
Official PYQ2015Theory of ComputationRegular Expressions and Finite AutomataNAT · 1 mark
The number of states in the minimal deterministic finite automaton corresponding to the regular expression (0+1)∗(10)(0+1)^* (10) is _____.
Official PYQ2015Computer NetworksFragmentation and IP Addressing, IPv4, CIDRMCQ · 1 mark
Host A\text{Host A} sends a UDP\text{UDP} datagram containing 8880 bytes8880\text{ bytes} of user data to host B\text{host B} over an Ethernet LAN.\text{Ethernet LAN}. Ethernet frames may carry data up to 1500 bytes (i.e. MTU = 1500 bytes).1500\text{ bytes (i.e. MTU = 1500 bytes)}. Size of UDP\text{UDP} header is 8 bytes8\text{ bytes} and size of IP\text{IP} header is 20 bytes.20\text{ bytes}. There is no …
Official PYQ2015Engineering MathematicsGraphs: Connectivity, Matching, ColouringMCQ · 1 mark
In a connected graph, a bridge is an edge whose removal disconnects the graph. Which one of the following statements is true?
Official PYQ2015Theory of ComputationRegular and Context-free LanguagesMCQ · 1 mark
Which of the following is/are regular languages? L1:{wxwR∣w,x∈{a,b}∗ and ∣w∣,∣x∣>0},wR is the reverse of string wL_1: \left\{ wxw^R \mid w, x \in \{a, b\} ^* \text{ and } |w|, |x| > 0\right\}, w^R \text{ is the reverse of string } w L2:{anbm∣m≠n and m,n≥0}L_2: \left\{ a^nb^m \mid m \neq n \text{ and } m, n \geq 0 \right\} L3:{apbqcr∣p,q,r≥0}L_3: \left\{ a^pb^qc^r \mid p, q, r \geq 0 \right\}
Official PYQ2015Operating SystemI/O SchedulingNAT · 1 mark
Consider a typical disk that rotates at 1500015000 rotations per minute (RPM) and has a transfer rate of 50×10650 \times 10^6 bytes/sec. If the average seek time of the disk is twice the average rotational delay and the controller's transfer time is 1010 times the disk transfer time, the average time (in milliseconds) to read or write a 512512-byte sector of …
Official PYQ2015Digital LogicComputer ArithmeticNAT · 1 mark
A half adder is implemented with XOR and AND gates. A full adder is implemented with two half adders and one OR gate. The propagation delay of an XOR gate is twice that of an AND/OR gate. The propagation delay of an AND/OR gate is 1.21.2 microseconds. A 44-bit-ripple-carry binary adder is implemented by using four full adders. The total propagation time …
Official PYQ2015Operating SystemMemory Management and Virtual MemoryNAT · 1 mark
A computer system implements 8  kilobyte8\;\text{kilobyte} pages and a 32-bit32\text{-bit} physical address space. Each page table entry contains a valid bit, a dirty bit, three permission bits, and the translation. If the maximum size of the page table of a process is 24  megabytes24\;\text{megabytes}, the length of the virtual address supported by the system is _______ …
Official PYQ2015DatabasesTransactions and Concurrency ControlMCQ · 1 mark
Consider a simple checkpointing protocol and the following set of operations in the log. (start, T4); (write, T4, y, 2, 3); (start, T1); (commit, T4); (write, T1, z, 5, 7); (checkpoint); (start, T2); (write, T2, x, 1, 9); (commit, T2); (start, T3); (write, T3, z, 7, 2); If a crash happens now and the system tries to recover using both undo and redo …
Official PYQ2015AlgorithmsSearching, Sorting, HashingMCQ · 1 mark
Suppose you are provided with the following function declaration in the C programming language. int partition(int a[], int n); The function treats the first element of a[ ]a[\:] as a pivot and rearranges the array so that all elements less than or equal to the pivot is in the left part of the array, and all elements greater than the pivot is in the right …
Official PYQ2015Computer Organization and ArchitectureInstruction PipeliningNAT · 1 mark
Consider the sequence of machine instruction given below: MULR5, R0, R1DIVR6, R2, R3ADDR7, R5, R6SUBR8, R7, R4\begin{array}{ll} \text{MUL} & \text{R5, R0, R1} \\ \text{DIV} & \text{R6, R2, R3} \\ \text{ADD} & \text{R7, R5, R6} \\ \text{SUB} & \text{R8, R7, R4} \\ \end{array} In the above sequence, R0R0 to R8R8 are general purpose registers. In the instructions shown, the first register …
Official PYQ2015Software Engineering (Historical)MCQ · 1 mark
Which one of the following assertions concerning code inspection and code walkthrough is true?
Official PYQ2015Computer Organization and ArchitectureMachine Instructions and Addressing ModesMCQ · 1 mark
Consider a processor with byte-addressable memory. Assume that all registers, including program counter (PC) and Program Status Word (PSW), are size of two bytes. A stack in the main memory is implemented from memory location (0100)16(0100)_{16} and it grows upward. The stack pointer (SP) points to the top element of the stack. The current value of SP is …
Official PYQ2015Computer NetworksFragmentation and IP Addressing, IPv4, CIDRMCQ · 1 mark
Consider the following routing table at an IP router: …