2003 Academic Challenge

Transcription

1 Worldwide Youth in Science and Engineering 2003 Academic Challenge COMPUTER SCIENCE TEST - STATE FINALS Computer Science Test Production Team S. R. Subramanya, University of Missouri - Rolla Author/Team Coordinator Jennifer Leopold, University of Missouri - Rolla Author Sanjay Madria, University of Missouri - Rolla Author Scott Elliott, John A. Logan College Reviewer Don Wayman, WYSE Coordinator of Test Production GENERAL DIRECTIONS Please read the following instructions carefully. This is a timed test; any instructions from the test supervisor should be followed promptly. The test supervisor will give instructions for filling in any necessary information on the answer sheet. Some Academic Challenge test sites are using answer sheets that require you to fill in the letter of the answer you choose on the blank line after each question number. Others may ask you to indicate your answer to each question by marking an oval that corresponds to the correct answer for that question. Only one oval should be marked to answer each question. Multiple ovals will automatically be graded as an incorrect answer. Be sure ovals are marked as. Not as,,. Test Question - 1. What is the name of the robotic helicopter used for surveillance by the U. S. Army? a. Eye in the Sky b. ROBOT I c. Surveyor I d. CYPHER e. Robospierre Answer Sheet-- 1. If you wish to change an completely before marking your new choice. A B C E answer, erase your first mark You are advised to use your time effectively and to work as rapidly as you can without losing accuracy. Do not waste your time on questions that are too difficult for you. Go on to the other questions and come back to the difficult ones later if you can. *** TIME: 40 MINUTES *** DO NOT OPEN TEST BOOKLET UNTIL YOU ARE TOLD TO DO SO! 2003 Worldwide Youth in Science and Engineering WYSE, Worldwide Youth in Science and Engineering and the WYSE Design are service marks of and this work is Copyright 2003 Board of Trustees of the University of Illinois at Urbana - Champaign. All rights reserved.

2 WYSE Academic Challenge Computer Science Test (State Finals) A CPU designed using a RISC architecture allows A) Assembly language programs to be written more easily. B) Emphasis on software support for execution of instructions C) The processor to run at a faster clock speed. D) All of the above. E) None of the above. 2. In the process of normalizing a floating-point number, when the radix point of the mantissa is shifted left, then the exponent is A) Decreased by the number of positions the mantissa is shifted. B) Increased by the number of positions the mantissa is shifted. C) Divided by 2. D) Unchanged. E) Divided by In an n-bit one s complement representation, A) 2 n - 1 integers can be represented. B) An end-around carry is required when performing addition. C) Negation is performed by complementing every bit. D) 0 has two representations. E) All of the above are true. 4. An overflow has occurred when adding two s complement numbers, if A) There is a carry out of the most significant bit (MSB). B) There is a carry into the MSB. C) The carry into the MSB differs from the carry out of the MSB. D) The carry into the MSB equals the carry out of the MSB. E) All of the above. 5. If all variables are of type integer and if a = b (mod m) and x = y (mod m), which of the following must be true? I. a + x = b + y (mod m) II. ax = by (mod m) III. a/n = b (mod m)/n for all n!= 0 A) II only B) III only C) I and II only D) I and III only E) I, II, and III

3 Computer Science 2 6. What is the number of terminal strings of length 5 generated by the context-free grammar shown below? A) 4 B) 5 C) 6 D) 7 E) 8 S --> A0B A --> BB 0 B --> AA 1 7. A relation can be defined by giving the ordered pairs of elements for which the relation holds. If the relation R over {a, b, c} is given by R = {(a,a), (a,b), (b,a), (b,b), (c,c)}, which of the following properties does R have? I. Symmetry II. Antisymmetry III. Reflexivity IV. Transitivity A) None. B) II and III only. C) II and IV only. D) I, III, and IV only. E) III and IV only. 8. Of the following components of a computer, which one stores data and instructions? A) Input device. B) Output device. C) Arithmetic/logic unit. D) Control unit. E) Memory unit.

4 9. What is the output of the following algorithm when objects stored in the array A [1.7] are 15, 1, 18, 5, 6, 9, 0, where N is 7. FUNCTION FUNC(A, N) J= 1; REPEAT MIN = INDEX_OF_MINIMUM in (A[J]...A[N]); SWAP A[J], A[MIN]; J= J+1; UNTIL J > N; RETURN A; A) 18, 15, 9, 6, 5, 1, 0 B) 18, 15, 9, 0, 1, 5, 6 C) 0, 1, 5, 6, 18, 15, 9 D) 0, 1, 5, 6, 9, 15, 18 E) None of the above. 10. What is the following sorting algorithm called? FUNCTION FUNC (A, N) I = 1 REPEAT WHILE I < N IF A[I] > A[I+1] THEN SWAP A[I], A[I+1]; END IF; I = I +1 ; END WHILE; UNTIL I >N; A) Bubble sort. B) Bucket sort. C) Insertion sort. D) Dummy sort. E) Quick sort. Computer Science 3

5 Computer Science What is the number produced by the following function for N = 10? A) 51 B) 45 C) 55 D) 53 E) 33 FUNCTION FUNC(N) IF N == 1 OR N == 2 THEN RETURN 1; ELSE X = FUNC(N-1) + FUNC(N-2); RETURN X; 12. What will the function print for N =3 if we read C as x then y then z on each execution of the following function? A) xyzzyx B) xxyzzy C) xyzxyx D) yzxyxx E) yzxzyz FUNCTION FUNC(N) IF N == 0 THEN RETURN; ELSE READ C; PRINT C; FUNC(N-1); PRINT C; 13. What will be the output of the following function for integer N >= 0? FUNCTION FUNC( N ) IF N == 0 THEN PRINT 0; RETURN; ELSE PRINT N; FUNC( N- 1); PRINT 2N 1; PRINT 2N; A) Numbers from 0 to 2N. B) Numbers from N to 0 and from 1 to 2N.

6 C) Numbers from 2N to 0. D) Numbers 0, N, 2N 1 and 2N. E) All of the above. Computer Science What will be the output of the following function for N>=0, where N is an integer number? A) 2 N B) N 2 C) 2N D) 2(N-1) E) 0 FUNCTION FUNC ( N ) IF N == 0 RETURN 1; ELSE RETURN (2 * FUNC( N-1 )); END FUNC 15. The following function is equivalent (in its closed form) to 0 if n = 0 f( n) = 2 + f( n 1) if n > 0 A) f(n) = 2(n-1) B) f(n) = 0 C) f(n) = 2n D) f(n) = 2 +f(n-1) E) None of the above. 16. The three levels of programming languages in order from the most machine-oriented to the most human-oriented are. A) Machine language, high-level language, and assembly language. B) Machine language, high-level language, and binary representation. C) Binary representation, machine language, and assembly language. D) Machine language, assembly language, and high-level language. E) Binary representation, assembly language, and machine language. 17. If you used the formula length + width to calculate the area of a rectangle (when it should be length * width), you would have made a error. A) Logical. B) Syntax. C) Pseudocode. D) Debugging. E) Lexical.

7 Computer Science In what order will the following function traverse the tree? A) Preorder B) Postorder C) Inorder D) Semiorder E) Sequential order FUNCTION FUNC(TREE) IF TREE IS NULL, RETURN; PRINT(TREE.ROOT); FUNC(TREE.LEFT_SUBTREE); FUNC(TREE.RIGHT_SUBTREE); 19. In what order will the following function traverse the tree? FUNCTION FUNC(TREE) IF TREE IS NULL, RETURN; FUNC(TREE.LEFT_SUBTREE); PRINT(TREE.ROOT); FUNC(TREE.RIGHT_SUBTREE); A) Preorder. B) Postorder. C) Inorder. D) Semiorder. E) Sequential order. 20. One difference between a queue and a stack is: A) Queues require linked lists, but stacks do not. B) Stacks require linked lists, but queues do not. C) Queues use two ends of the structure; stacks use only one. D) Stacks use two ends of the structure, queues use only one. E) Stacks and Queues both are data structures to store data. 21. If the characters 'D', 'C', 'B', 'A' are placed in a queue (in that order), and then removed one at a time, in what order will they be removed? A) ABCD B) ABDC C) DCAB D) DCBA E) BADC

8 Computer Science The traversal of the following tree in order of 3 * ^ 2 is called + * ^ A) Breath First Serach B) Preorder C) Inorder D) Postorder E) Depth First Search The sum of the first n powers of 2; n, n>=0, is A) 2 (n+1) -1 B) 2 n + 1 C) 2 n 1 D) 2n(n+1) E) 2n The worst-case time complexity of the code below is: FOR I = 0 to 200 DO N = 2*4; A) O(1) B) O(N) C) O(N 2 ) D) O(N log(n)) E) O(log(N)) 25. What are some advantages of increasing the modularity of code? A) To organize your code (programming style). B) To avoid repeating code if several executions needed. C) To increase the complexity of your code. D) Both a, and b. E) Both a, and c. 26. The Boolean expression XY + X Y is equivalent to A) X B) X +Y

9 C) Y D) XY E) None of the above. Computer Science The Boolean expression ( B C + AD)( AB + CD) is equal to A) 0 B) BC C) AB D) CD E) BC + CD 28. In the following logic diagram, F is equal to A) Y Z + Y( W + X ) B) (Y + Z) (W+ X) C) Y Z + Y( W + X ) D) Y Z + Y( W + X ) E) ZY + ( W + X ) 29. The result of Subtracting 0001 from 0111 using 2's complement is A) B) -6 C) 1001 D) 1100 E) All of the above. 30. For all x < 1, 3 ln{(1 x) } + is equal to A) x 3 - x 6 /2 + x 9 /3 - x 12 / B) 3(x - x 2 /2 + x 3 /3 - x 4 / C) 3(1 + x 3 - x 6 /2 + x 9 /3 - x 12 /4 +...) D) 1 + 3(x - x 2 /2 + x 3 /3 - x 4 /4 +...

10 E) None of the above.