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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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Official PYQ2015Digital LogicNumber Representations (Fixed and Floating Point)NAT · 1 mark
Consider the equation (43)x=(y3)8(43)_x = (y3)_8 where xx and yy are unknown. The number of possible solutions is _____
Official PYQ2015Operating SystemCPU SchedulingMCQ · 1 mark
For the processes listed in the following table, which of the following scheduling schemes will give the lowest average turnaround time? …
Official PYQ2015Theory of ComputationContext-free Grammars and Push-down AutomataMCQ · 1 mark
Which of the following languages are context-free? L1:{ambnanbm∣m,n≥1}L_1: \left\{a^mb^na^nb^m \mid m, n \geq 1\right\} L2:{ambnambn∣m,n≥1}L_2: \left\{a^mb^na^mb^n \mid m, n \geq 1\right\} L3:{ambn∣m=2n+1}L_3: \left\{a^mb^n \mid m = 2n +1 \right\}
Official PYQ2015Engineering MathematicsLinear Algebra: Matrices, Determinants, System of Linear EquationsMCQ · 1 mark
If the following system has non-trivial solution, px+qy+rz=0px + qy + rz = 0 qx+ry+pz=0qx + ry + pz = 0 rx+py+qz=0rx + py + qz = 0, then which one of the following options is TRUE?
Official PYQ2015Compiler DesignParsing (LL, LR)MCQ · 1 mark
Consider the following grammar G S→F∣HS \rightarrow F \mid H F→p∣cF \rightarrow p \mid c H→d∣cH \rightarrow d \mid c Where SS, FF, and HH are non-terminal symbols, p,dp, d, and cc are terminal symbols. Which of the following statement(s) is/are correct? S1: LL(1) can parse all strings that are generated using grammar G S2: LR(1) can parse all …
Official PYQ2015Programming and Data StructuresArrays, Stacks and QueuesMCQ · 1 mark
Consider the following two C code segments. YY and XX are one and two dimensional arrays of size nn and n×nn \times n respectively, where 2≤n≤102 \leq n \leq 10. Assume that in both code segments, elements of YY are initialized to 00 and each element X[i][j]X[i][j] of array XX is initialized to i+ji+j. Further assume that when stored in main …
Official PYQ2015DatabasesTransactions and Concurrency ControlMCQ · 1 mark
Consider the partial Schedule SS involving two transactions T1T1 and T2T2. Only the read\textit{read} and the write\textit{write} operations have been shown. The read\textit{read} operation on data item PP is denoted by read(P)\textit{read(P)} and write\textit{write} operation on data item PP is denoted by write(P)\textit{write(P)}. …
Official PYQ2015Computer NetworksTransport Layer: Flow Control, Congestion Control, UDP, TCP, SocketsNAT · 1 mark
Consider a network connecting two systems located 80008000 Km\text{Km} apart. The bandwidth of the network is 500×106500 \times 10^6 bits\text{bits} per second. The propagation speed of the media is 4×1064 \times 10^6 meters\text{meters} per second. It needs to design a Go-Back-NN sliding window protocol for this network. The average packet size is 10710^7 …
Official PYQ2015Programming and Data StructuresProgramming in CNAT · 1 mark
Consider the following C program #include<stdio.h> int main() { static int a[] = {10, 20, 30, 40, 50}; static int *p[] = {a, a+3, a+4, a+1, a+2}; int **ptr = p; ptr++; printf("%d%d", ptr-p, **ptr); } The output of the program is _______.
Official PYQ2015AlgorithmsSearching, Sorting, HashingMCQ · 1 mark
Assume that a mergesort algorithm in the worst case takes 3030 seconds for an input of size 6464. Which of the following most closely approximates the maximum input size of a problem that can be solved in 66 minutes?
Official PYQ2015Programming and Data StructuresTreesNAT · 1 mark
Consider a binary tree T that has 200200 leaf nodes. Then the number of nodes in T that have exactly two children are ______.
Official PYQ2015Engineering MathematicsPropositional and First Order LogicMCQ · 1 mark
In a room there are only two types of people, namely Type 1\text{Type 1} and Type 2\text{Type 2}. Type 1\text{Type 1} people always tell the truth and Type 2\text{Type 2} people always lie. You give a fair coin to a person in that room, without knowing which type he is from and tell him to toss it and hide the result from you till you ask for it. Upon asking the …
Official PYQ2015Engineering MathematicsSets, Relations and FunctionsMCQ · 1 mark
Suppose UU is the power set of the set S={1,2,3,4,5,6}S = \{1, 2, 3, 4, 5, 6\}. For any T∈UT \in U, let ∣T∣|T| denote the number of elements in TT and T′T' denote the complement of TT. For any T,R∈U let T\RT, R \in U \text{ let } T \backslash R be the set of all elements in TT which are not in RR. Which one of the following is true?
Official PYQ2015Computer NetworksTransport Layer: Flow Control, Congestion Control, UDP, TCP, SocketsMCQ · 1 mark
Consider the following statements. TCP connections are full duplex TCP has no option for selective acknowledgement TCP connections are message streams
Official PYQ2015Software Engineering (Historical)NAT · 1 mark
Consider a software project with the following information domain characteristics for calculation of function point metric. Number of external inputs (I) = 30 Number of external outputs (O) = 60 Number of external inquiries (E) = 23 Number of files (F) = 08 Number of external interfaces (N) = 02 It is given that the complexity weighting factors for I, O, E, …
Official PYQ2015DatabasesNormal FormsMCQ · 1 mark
Consider the relation X(P,Q,R,S,T,U)X(P,Q,R,S,T,U) with the following set of functional dependencies F={    {P,R}→{S,T},    {P,S,U}→{Q,R}  }F = \{ \\ \; \; \{P, R\} \rightarrow \{S, T\}, \\ \; \; \{P, S, U\} \rightarrow \{Q, R\} \\ \; \} Which of the following is the trivial functional dependency in F+F^+, where F+F^+ is closure to F?
Official PYQ2015Programming and Data StructuresBinary HeapsMCQ · 1 mark
Consider the following array of elements. ⟨89,19,50,17,12,15,2,5,7,11,6,9,100⟩\langle 89, 19, 50, 17, 12, 15, 2, 5, 7, 11, 6, 9, 100 \rangle The minimum number of interchanges needed to convert it into a max-heap is
Official PYQ2015Theory of ComputationRegular Expressions and Finite AutomataMCQ · 1 mark
Let LL be the language represented by the regular expression Σ∗0011Σ∗\Sigma^*0011\Sigma^* where Σ={0,1}\Sigma = \{0, 1\}. What is the minimum number of states in a DFA that recognizes Lˉ\bar{L} (complement of LL)?
Official PYQ2015Programming and Data StructuresArrays, Stacks and QueuesNAT · 1 mark
Given that hash table TT with 2525 slots that stores 20002000 elements, the load factor aa for TT is _________.
Official PYQ2015Compiler DesignParsing (LL, LR)MCQ · 1 mark
Among simple LR (SLR), canonical LR, and look-ahead LR (LALR), which of the following pairs identify the method that is very easy to implement and the method that is the most powerful, in that order?