4. Write the output that would be printed from each of the following code fragments. (8pts) x = 9 y = x / 2 print('y ==', y) +1 4.

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1 1. Write an X To the left of each valid Python name (identifier). (4pts) a) X pyhonindetfriar c) X a_b_c_d b) 9to5 d) x*y all or none 2. Write an X To the left of each Python reserved word (keyword). (4pts) a) _ X if c) Arizona b) four d) _ X for all or none 3. For each Python expression, indicate its value in the space to its left. Be sure to write a resulting value of the appropriate type. For example, 2.0 is different than 2 which is also different than '2'. (12pts) a) / 4 f) _ * 3 // 4 b) 3 14 // 4 g) _1.0 1 / 4 * 4 c) 2 14 % 4 h) _7.56 eval('7.56') all or none d) _ i) _456 eval('456') -1/2 if type is wrong (1 not 1.0) e) _'144' '14' + '4' j) % 50 % 25 (or 144 not '144') 4. Write the output that would be printed from each of the following code fragments. (8pts) x = 9 y = x / 2 print('y ==', y) a, b = 5, 9 b, a = a, b print(a, b) n = 4 for i in range(1, n + 1, 1): print(i, end=' ') y == For each Python expression, indicate its value in the space to its left. Be sure to list a resulting value of the appropriate type. For example, 2.0 is different than 2. Assume import math (6pts) a) 3.0 math.sqrt(9.0) d) 3.46 round( , 2) all or none b) 3 abs(5-8) e) 3.5 min(3.5678, 3.5) -1/2 if type is wrong (3 not 3.0) c) 3.0 abs( ) f) -3 max(-5, -3) 6. Write the complete dialog (input and output) from this program when the user enters for x followed by for y. (4pts) x = int(input('x? ')) y = int(input('y? ')) print('max: ', max(x, y)) print('min: ', min(x, y)) 7. Write a complete Python program that reads two test scores and prints the average of the two. Your dialog should look like this when the user enters 90.0 followed by (6pts) Test1? Test2? Average: 85.5 x? 5 1 pt for each correct line y? 6-1 for wrong value after Min or Max Max: 6-1/2 for any missing label like x? Min: 5 t1 = eval(input('test1? ')) t2 = eval(input('test2? ')) print('average:', (t1+t2)/2) 1 used eval or float 1 used input 1 prompts correct 1 prints Average and a number 2 formula for average correct (t1+t2/2 is not) 1

2 8. Write the output generated by the following code. (4pts) a = 20; b = 8; if a % 10 == 0: b = b * 10 a = a + 10 if a < b: b = b + 5 three All or none print(a, b) 9. For each Python expression, write True if the expression evaluates to true. Write False if the expression evaluates to false. Assume the following variables always have the values shown. (6pts) s = 'algorithm' n = 12 x = 99.9 a) False n == 12 d) _ False s >= 'apple' and s <= 'zebra' b) False x >= e) _True not(s.upper() == 'Algorithm') All or none c) True 10 <= n <= 16 f) True s[2:4] + s[4:6]=='gori' 10. Given 2 integers, complete function to if both arguments are in the range inclusive. Return False if either is not in the range of (10pts) (a, b): return (0 <= a <= 100) and (0 <= b <= 100) -or more commonly- if (0 <= a <= 100) and (0 <= b <= 100) else return False +3 Expression correct for a 0 <= a <= Expression correct for b 0 <= b <= Use if else to distinguish or return the Boolean Expression +1 returns True somewhere/somehow +1 returns False somewhere/somehow 11. Given three integers, complete (a, b, c) to if any one integer parameters is 10 or more than either of the other two. Only any two integers need to differ by 10 or more to. (12pts) p1 = abs(a-b) >= 10 p2 = abs(a-c) >= 10 p3 = abs(b-c) >= 10 return p1 or p2 or p3 maximum = max(max(a,b),c) minimum = min(min(a,b),c) return maximum - minimum >= 10 # Most common solution if abs(a - b) >= 10: if abs(a - c) >= 10: if abs(c - b) >= 10: return False 2

3 12. Write the output generated by the following code (2pts) s = 'Madison' if s < 'D': print('one') elif s < 'M': print('two') elif s < 'Q': print('three') three (all or none) print('four') 13. Complete function (day) to return the string 'WeekEnd' if the argument day is 6 or 7 or return the string'weekday' if the argument day is 1, 2, 3, 4, or 5. If day is outside the range of 1 through 7 return '??'. (12pts) weekendorday(1) returns 'WeekDay' weekendorday(5) returns 'WeekDay' weekendorday(6) returns 'WeekEnd' weekendorday(7) returns 'WeekEnd' weekendorday(0) returns '??' weekendorday(8) returns '??' (day): if day <= 0 or day >= 8: return '??' elif 1 <= day <= 5: return 'WeekDay' return 'WeekEnd' 14. For each Python expression, indicate its value in the space to its left. Assume the string type variable s is assigned the string value 'park union'. Use ' ' when the expression evaluates to a string. (4pts) s = 'park union' a) 'ru' s[2:3] + s[5] c) 3 len(s[1:4]) b) _ 'paun'_ s[0:2] + s[5:7] d) 20 2 * len(s) All or none ' ' not needed 15. Complete (s) to return the middle two characters of s. When the length of s is odd, favor the left. (8pts) ('A') middletwo('ab') middletwo('abc') middletwo('abcd') middletwo('abcde') returns 'A' returns 'AB' returns 'AB' returns 'BC' returns 'BC' (s): if len(s) <= 2: return s mid = len(s) // 2-1 return s[mid:mid+2] +1 returns anything +1 returns any part of string +2 returns exactly a string of length 2 +3 returns the correct two characters +1 Grader discretion / No syntax error 3

4 16. How many times will each code fragment print 'Hello '? 0 and infinite are legitimate answers. (12pts, 3 pts each) n = 1 for lcv in range(n): print('hello '); 1 n = 6; c = 0; while c <= n: print('hello ') c = c for lcv in range(5): print('hello ') 5 # Tricky All or none n = 5 c = 1 while c <= n: print('hello ') infinite c = Write the output generated by this Python code. (4pts) s = 'UOA' for index in range(len(s) - 1): print(s[index], '_', s[len(s) - index - 1]) U _ A O _ O +1 for each letter U A O O -2 for 3rd line 18. Complete function (s) to return how often the string 'Abba' occurs in s. This is case insensitive so any mix of upper and lower case 'AbBa' must count as 1 occurrence. 'Abba' may overlap. (12pts) howswedish('') returns 0 howswedish('abb') returns 0 howswedish('abba_abba') returns 2 howswedish('abba') returns 1 howswedish('abbabba') returns 2 (overlap) howswedish('abbabbabba')returns 3 (overlap) howswedish('abnotba') returns 0 ('Abba' must be consecutive, 'abba' cannot be split with other characters) (s): result = 0 s = s.upper() for i in range(len(s) - 3): if s[i:i+4] == 'ABBA': result += 1 return result +2 Maintains a count (r to the left) 1 initialize to 0 +1 Loop exists +3 Comparison to 'ABBA' ('abba' if lower() used) 1 if 1 == 1 correct string slicing +2 Case insensitive 4

5 19. For each Python expression, indicate its value in the space to its left. Assume the following list type variable list always has the assigned value of [-9, 1, 9, 3, 4] (4pts) list = [-9, 1, 9, 3, 4] a) 1 list[1] d) 0 list[0] + list[2] All or None b) 5 len(list) e) 3 list[len(list)-2] 20. Complete function to return the sum of all odd integers in the given list, including negative integers. If there are no odd numbers in list, return 0. (12pts) ( [1, 2] ) returns 1 sumallodds( [1, 2, 3, 4] ) returns == 4 sumallodds( [-3, -2, -1] ) returns == -4 sumallodds( [-99] ) returns -99 sumallodds( [] ) returns 0 (when len(list) == 0 return 0) sumallodds( [2, 4, 6] ) returns 0 (list has no odds, so return 0) (list): sum = 0 for i in range(len(list)): if list[i] % 2!= 0: sum += list[i] return sum +3 Maintains sum 1 initialize to 0 2 adds list element when appropriate +3 Loop 1 exists 1 syntax 1 upper bound exclusive is len(list) +5 Decision 1 if exists 4 determine odd numbers correctly indexes list element with [] logic correct (True when odd) +1 returns Special case: -2 returning too early 5