4. Write the output that would be printed from each of the following code fragments. (6pts) a = 5 b = 4 temp = a a = b b = temp print(a, b, temp)

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1 1. Write an X To the left of each valid Python names (identifiers). (6pts) a) _ X_ mispelted e) _ X_ t_rex b) _ X_ ident999 f)??? c) 25or6to4 g) H.P. 2. Write an X To the left of each Python reserved words (keywords). (6pts) a) UofA e) _ X_ False b) mercer f) J.C Penney c) false g) _ X_ 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'. (14pts) a) 10 5 * 2 i) // 3 b) 2 5 // 2 j) (int)(14.0 / ( )) c) / 2 k) 123 eval('123') // Hardcopy was missing ' ' e) l) 1.23 eval('1.23') f) m) float(123) g) '52' '5' + '2' n) 0 10 % (4 + 6) / 2 h) 25 5**2 o) % 2 / Write the output that would be printed from each of the following code fragments. (6pts) x = 5 y = 7.3 print('answer', x + y) 12.3 a = 5 b = 4 temp = a a = b b = temp print(a, b, temp) for i in range(3): print(i, end=' ') For each Python expression, indicate its value in the space to its left. Be sure to list a resulting value of appropriate type. For example, 2.0 is different than 2. Assume import math (4pts) a) 2.0 math.sqrt(4.0) c) 3 round( ) b) 3 round(math.pi) d) 6.79 round( , 2) 6) Write the complete dialog (input and output) from this program when the user enters 56 (4pts) number = int(input('number? ')) number = number // 10 Number? 56 1

2 number = number % 3 2 print(number) 7) Write a complete Python program that reads an integer representing change to and prints how many dimes (10 cents) and pennies will make that change. You only have dimes and pennies to, no quarters or nickels. Use the given dialog to guide your algorithm and code. (8pts) Change? Dimes: 9 Pennies: 7 # Write the complete program below this line. Do not use main(): change = int(input('change? ')) dimes = change // 10 pennies = change % 10 print('dimes:', dimes) print('pennies:', pennies) 8. Write the output generated by the following code. (4pts) j, k = 0, 1 if j!= k: print('abc') if j == k: print('') if j <= k: print('ghi') if j >= k: print('klm') abc ghi 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. (8pts) s = 'euclid' n = 5 x = a) True n == 5 e) True s > 'any' and s < 'zero' b) False x > n f) False not(s == 'euclid') c) True x <= and x >= 0.0 g) True s[0] == 'e' and s[2] == 'c' d) True x!= n h) False s[1:3] == 'ucl' 10. Given 2 integers, complete function to true if both arguments are in the range inclusive, or they are both in the range inclusive. (10pts) s in3050(30, 31) s True in3050(40, 50) s True in3050(39, 49) s False in3050(30, 41) s False (a, b): range1 = 30 <= a <= 40 and 30 <= b <= 40 range2 = 40 <= a <= 50 and 40 <= b <= 50 range1 or range2 2

3 11. For each Python expression, indicate its value in the space to its left. Assume the following string type variable s is assigned the string value 'main gate'. Use ' ' when the expression evaluates to a string. (4pts) s = 'main gate' a) 'm' s[0] d) 'MAIN GATE' s.upper() b) 'ai' s[1:3] e) 5 s.find('gate') 12. Given the string argument str, complete function to take the first 2 chars of str and a string with both chars added at both the front and back, so 'kitten' yields 'kikittenki'. len(str) is always 2 or more. (8pts) front22('cat') s 'cacatca' front22('to') s 'tototo' (s): s[0:2] + s + s[0:2] 13. Write the output generated by the following code (2pts) s1 = 'B'; if s1 >= 'D': print('one') elif s1 >= 'C': print('two') elif s1 >= 'B': print('three') print('four') three (day): if day < 1 or day > 7: 14. Given the integer argument day, complete elif day == function 1: (in the box to the right) to the string 'Mo' if day is 1, 'Tu' if day is 2, and so on. If day is any other integer outside the range of 1 through 7 '??'. (12pts) elif day == 2: dayofweek(3) s 'We' dayofweek(4) s 'Th' dayofweek(5) s elif day == 3: 'Fr' dayofweek(6) s 'Sa' dayofweek(7) s 'Su' elif day == 4: dayofweek(0) s '??' dayofweek(8) s '??' elif day == 5: elif day == 6: 3

4 15. How many times will each code fragment print 'Hello '? 0 and Infinite are legitimate answers (12pts, 3 pts each) n = 5 for lcv in range(n): 5 print('hello '); for j in range(1, 10, 3): print('hello ') 3 n = 1; c = 5; while c <= n: print('hello ') 0 c = c + 1 n = 5; c = 1; while c <= n: print('hello ') infinite 16. Complete function to the sum of all integers squared from 1 through n inclusive. (10pts) (1) s 1*1 = 1 sumofsquares(2) s 1*1 + 2*2 = 5 sumofsquares(5) s 1*1 + 2*2 + 3*3 + 4*4 + 5*5 = 55 (n): sum = 0 for i in range(1, n+1, 1): sum = sum + i*i sum 17 For each Python expression, indicate its value in the space to its left. Assume the following list type variable list is assigned the value [5, 4, 6, 2]. (4pts) list = [5, 4, 6, 2] a) 5 list[0] e) 10 list[1] + list[2] b) 4 len(list) f) 2 list[len(list)-1] 18. Complete method to how often an odd integer occurs in a list. (12pts) numberofodds([1, 2, 3, 4, 5]) s 3 numberofodds([2, 4]) s 0 numberofodds([-1, -3, -5, -7]) s 4 (list): result = 0 for i in range(len(list)): if list[i] % 2!= 0: result = result + 1 result 4

5 16. Complete function that given a string, looks for a mirror image (backwards) string at both the beginning and end of the given string. In other words, zero or more characters at the very beginning of the given string, and at the very end of the string in reverse order. For example, the string 'abxyzba' has the mirror end 'ab'. (16pts) ('') s '' mirrorends('abcde') s '' mirrorends('123456') s '' mirrorends('abca') s 'a' mirrorends('abcba') s 'ab' mirrorends('abccba') s 'abccba' there may be overlap (s): result = n = len(s) for i in range(n): if s[i] == s[n-i-1]: result = result + s[i] break # stop looking, A break statement cause the loop to terminate immediately, code jumps to the result # You should not need a while loop on the test, but the following solution could be easier to think of. # You certainly may use a while loop on the Midterm to solve any problem mirrorends(s): result = '' rightindex = len(s) - 1 leftindex = 0 while leftindex < len(s) and s[leftindex] == s[rightindex]: result = result + s[leftindex] leftindex = leftindex + 1 rightindex = rightindex - 1 result 5