GATE 2015 CS (CS3) – Previous Year Questions with Solutions
All 65 questions of GATE 2015 CS (CS3) with answers and explanations. Read each question, then practise it by topic or as a full paper.
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- Question 1 – Extreme focus on syllabus and studying for tests has become such a dominant concern of Indian students that they close their minds to anything to the…
- Question 2 – Choose the analogy closest to Children : Paediatrician.
- Question 3 – Fill the four blanks: The Tamil version of John Abraham-starrer Madras Cafe cleared by the Censor Board with no cuts last week, but the film’s…
- Question 4 – If ROAD is coded URDG, how is SWAN coded?
- Question 5 – A linear function f has f(−2)=29 and f(3)=39. Find f(5).
- Question 6 – Alexander turned his attention towards India, since he had conquered Persia. Which inference is intended?
- Question 7 – Experts felt that, despite possessing every technical skill needed for top-level batting, a batsman was unlikely to succeed because he lacked…
- Question 8 – The chart shows annual exports and imports in crores of rupees from 2000 to 2007. In which year was the combined percentage increase in imports and…
- Question 9 – Which equation describes the thick line in the plotted graph?
- Question 10 – Five of P,Q,R,S,T,U receive the portfolios Home,Power,Defense,Telecom,Finance. U refuses a portfolio if S gets one. R wants Home or Finance or no…
- Question 11 – What is printed?
- Question 12 – U is the power set of S=1,2,3,4,5,6. T is cardinality, T′ complement in S, and T∖R set difference. Which is true?
- Question 13 – For X(P,Q,R,S,T,U), F=PR→ST, PSU→QR. Which dependency in F⁺ is trivial?
- Question 14 – For a system with n CPUs, the maximum number of processes in the Ready state is
- Question 15 – Among SLR, canonical LR and LALR, select the method easiest to implement followed by the most powerful method.
- Question 16 – Define X\#Y=X+Y on Boolean variables. S1: (P#Q)#R=P#(Q#R). S2: Q#R=R#Q. Which hold?
- Question 17 – For function points: external inputs I=30, outputs O=60, enquiries E=23, files F=8, external interfaces N=2. Their weights are 4,5,4,10,7. Of fourteen…
- Question 18 – Ten server pages have URLs http://www.yourname.com/var.html, with var from 1 to 10. A local edited copy of page 1 contains relative links such as…
- Question 19 – Consider: I TCP connections are full duplex. II TCP has no selective-acknowledgement option. III TCP connections are message streams. Which are…
- Question 20 – For i=0n i3=X, consider I (n4), II (n5), III O(n5), IV (n3). Which may replace X?
- Question 21 – A binary tree has 200 leaves. How many nodes have exactly two children?
- Question 22 – A hash table with 25 slots stores 2000 elements. Find its load factor α.
- Question 23 – For M=pmatrix1&-1&2\\0&1&0\\1&2&1pmatrix, which vectors are eigenvectors for eigenvalue 1? α is any nonzero real number.
- Question 24 – Evaluate x(1+x2)e-x.
- Question 25 – How many four-digit numbers using only 1,2,3 have digits in nondecreasing order from left to right?
- Question 26 – A room contains truth-tellers and liars. An unknown person tosses a fair coin unseen and says: “The result is head if and only if I am telling the…
- Question 27 – Insert 71,65,84,69,67,83 into an empty binary search tree in this order. Which element is at the deepest level?
- Question 28 – Evaluate the postfix expression: 10 5 + 60 6 / * 8 − .
- Question 29 – Cinema(theater,address,capacity) stores theaters. Complete the query to always return addresses of maximum-capacity theaters, assuming non-NULL…
- Question 30 – Find the minimum number of interchanges needed to convert the level-order array [89,19,50,17,12,15,2,5,7,11,6,9,100] into a max-heap.
- Question 31 – Shared varP,varQ start false. These loops deliberately put the critical sections INSIDE the while bodies. Which property holds?
- Question 32 – Over Σ=0,1, let L be represented by Σ*0011Σ*. Find the minimum DFA-state count for its complement.
- Question 33 – A program is seeded with 100 artificial faults. Testing detects 159 faults, of which 75 are seeded. Assume real and seeded faults have the same…
- Question 34 – A byte-addressable machine has 220 bytes of memory, sixteen-byte blocks and a direct-mapped cache with 212 lines. Consecutive addresses include…
- Question 35 – A CSMA/CD network transmits at 100 Mbps over a 1 km cable without repeaters. Minimum frame size is 1250 bytes. Find the signal speed in km/s.
- Question 36 – A motorbike starts from rest. Its velocity v in km/min at times t in minutes is: t 2 4 6 8 10 12 14 16 18 20 --- --- --- --- --- --- --- --- --- ---…
- Question 37 – Worst-case mergesort takes 30 seconds for input size 64. Which best approximates the maximum size sortable in six minutes?
- Question 38 – How many calls to get, including the initial and base-case calls, occur for get(6)?
- Question 39 – A B+ tree has 12-byte search keys, 1024-byte blocks, 10-byte record pointers and 8-byte block pointers. Find the maximum keys in a nonleaf node.
- Question 40 – For F=P+QR, consider S1 F=(4,5,6); S2 F=(0,1,2,3,7); S3 F=(4,5,6); S4 F=(0,1,2,3,7). Which truth-value pattern applies?
- Question 41 – L1≤pL2, L3≤pL2 and L2≤pL4. Which are guaranteed? I: L4∈P implies L2∈P. II: L1∈P or L3∈P implies L2∈P. III: L1∈P iff L3∈P. IV: L4∈P implies L1,L3∈P.
- Question 42 – What is printed?
- Question 43 – What is printed?
- Question 44 – Which languages are context-free? L 1=\ambnanbm:m,n1\; L 2=\ambnambn:m,n1\; L 3=\ambn:m=2n+1\.
- Question 45 – Which policies prevent deadlock with mutually exclusive resources? I: Acquire all resources at the beginning; if any are unavailable, release all…
- Question 46 – In network 200.10.11.144/27, find the final octet of the last host-assignable IP address, in decimal.
- Question 47 – Two systems are 8000 km apart. Bandwidth is 500106 bits/s; propagation speed is 4106 metres/s; average packet size is 107 bits. Neglect processing…
- Question 48 – A pipeline reservation table uses S1 at times 1 and 5, S2 at times 2 and 4, and S3 at time 3. Find its minimum average initiation latency.
- Question 49 – Instructions have form OP Ri,Rj,Rk, writing Ri and reading Rj,Rk: S1: I2 and I5 have an anti-dependence. S2: I2 and I4 have an anti-dependence. S3: An…
- Question 50 – In C, Y has length n and X is n×n, 2≤n≤10. Initially Y is zero and X[i][j]=i+j; all of X lies in one memory page frame. Segment 1 loops i=0,…,n−1 with…
- Question 51 – A partial schedule is: Time T1 T2 --- --- --- 1 read(A) 2 write(A) 3 read(C) 4 write(C) 5 read(B) 6 write(B) 7 read(A) 8 commit 9 read(B) T1 fails…
- Question 52 – The homogeneous equations px+qy+rz=0, qx+ry+pz=0, rx+py+qz=0 have a nonzero real solution. Which condition follows for real p,q,r?
- Question 53 – How many times is printf executed?
- Question 54 – For nonzero x, af(x)+bf(1/x)=1/x-25, where a≠b. Find 12 f(x)\,dx, assuming the parameters make the equations nonsingular.
- Question 55 – A connected undirected graph has 100 vertices and 300 edges. Its minimum spanning-tree weight is 500. Every edge weight is increased by five. Find the…
- Question 56 – Two hosts connect through one packet switch using 107 bits/s links. Each link has 20 μs propagation delay. The switch begins forwarding a packet 35 μs…
- Question 57 – Processes have (arrival,processing) times A=(0,3), B=(1,6), C=(4,4), D=(6,2). Which policy gives the lowest average turnaround time?
- Question 58 – Program X and the control-flow diagrams of Y and sequential composition Z are shown. Give their McCabe cyclomatic complexities in order.
- Question 59 – For unknown number bases x and y, (43)ₓ=(y3)₈. How many integer solutions (x,y) are possible?
- Question 60 – On ordered pairs of positive integers, ((p,q),(r,s))∈R iff p−s=q−r. Which describes R?
- Question 61 – X1,X2,X3 are independent, each equally likely zero or one. Y=(X1X2) XOR X3, where juxtaposition denotes multiplication. Find P(Y=0 X3=0).
- Question 62 – Find the number of prime implicants of f(w,x,y,z)=Σ(0,2,4,5,6,10).
- Question 63 – Find DOSOMETHING(c,a,n) for k=4,c=(1,0,1,1),a=2,n=8.
- Question 64 – For positive integer n, f(n)=n and g(n)=n1+ n. Which hold? I: f=O(g). II: f=Ω(g).
- Question 65 – Grammar G has S→F H, F→p c, H→d c. S1: LL(1) can parse every string using grammar G. S2: LR(1) can parse every string using grammar G. Which are…