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Exam 1 Practice - Intro to Computer Programming

Evaluate expressions

Evaluate the following expressions and note the data type of the result:

Expression Evaluates To Data Type 5 * 2 5 ** 2 '5' + '2' '5' * 2 5 / 2 5 // 2 5 % 2 5 + 2.0 5.0 * 2.0 10 > 2 2 < 1 2 != 4 4 == 2**2 'cat' < 'dog' 'Cat' < 'dog' 5 > 2 and 10 > 11 5 > 2 or 10 > 11 5 > 2 and not (10 > 11) str.lower('HeLLo') str.upper('HeLLo') format(5.1, '.2f') format(5.1, '>10.2f') random.randint(1,5) len('cat') len('cat' + 'dog') not (5>2 and 5 < 4)

Input/Output

What is the exact output of each of the following programs? - Try and determine this by reading only, without running the programs.

Program #1

a = 10
b = 20
c = 30

if c > b + a:
 print ("NnYnUn")

else:
 if b + a >= c:
 print ("CnOnUnRnAnNnTn")
 else:
 print ("SnTnEnRnNn")

print (a,b,c)

Program #2

x = 'cupid'
z = 'arrow'

if x < z:
 t = x
 x = z
 z = t

v = x + " <--> " + z

if ( ( (5 + 2 >= 6.0) and (1.0 < 0.5) ) or True):
 print (x,z,v, sep='t')
else:
 print (v,z,x, sep='n')

Program #3

a = 5
b = 6
c = 20
d = 24

if a < b and b * 2 < c:

 print ("Python Case 1")
 print ("A", 't', "B", 't', "C")

 if a * 2 == c:
 print (a*2, 't', a*2, 't', a*2)
 elif a * 3 == c:
 print (a*3, 't', a*3, 't', a*3)
 elif a * 4 == c:
 print (a*4, 't', a*4, 't', a*4)
 else:
 print ('?', 't', '?', 't', '?')

else:

 print ("Python Case 2")
 print ("a", 't', "b", 't', "c")

 if b * 2 == d:
 print (b*2, 't', b*2, 't', b*2)
 elif b * 3 == d:
 print (b*3, 't', b*3, 't', b*3)
 elif b * 4 == d:
 print (b*4, 't', b*4, 't', b*4)
 else:
 print ('?', 't', '?', 't', '?')

Program #4

def fun1():
 print ("hi!")

def fun2():
 print ("bye!")

if 10 < 5 or 5 > 6:
 fun1()
 fun2()
else:
 fun2()
 fun1()

Write programs from scratch

Use your programming skills to solve the following programming challenges:

  1. Write a program that asks the user to supply two words. Sort the words in alphabetical order and print them back to the user.
  2. Write a program that asks the user to supply two words. Sort the words in size order and print them back to the user.
  3. Write a program that has the computer virtually roll two 6 sided dice. Output the result as follows: "Virtual dice roll: 3 and 5"
  4. Write a program that asks the user to enter in number. Then have the computer generate a random number and compare the result. If the numbers are the same print out a "You Win!" message. If not, print out a "Try Again" message.
  5. Write a program that qualfies the user for a particular credit card. Users must meet the following criteria:
    • Make at least $30,000 per year
    • Their rent payment must not be more than 5% of their total salary per month (i.e. 1,500 is the max rent that they can pay while making 30,000 per year)
    • However, if they own their home you do not need to take their monthly house payment into accountHere is a sample running of the program:
Credit card qualifier
How much do you make per year? 30000
Do you own your home? (y/n) y
You qualify!

Credit card qualifier
How much do you make per year? 35000
Do you own your home? (y/n) n
How much do you pay in rent per month? 1000
You qualify!

Credit card qualifier
How much do you make per year? 50000
Do you own your home? (y/n) n
How much do you pay in rent per month? 5000
Sorry, you don't qualify. Your rent is too high
  1. Write a program to ask a user to enter in 3 test scores (0-100) and 1 homework score (0-100). Then calculate the user's grade using the following formula - Tests: 50%, Homework: 50%. You can assume the user will enter integer values. Print out the grade as a number (i.e. 78.56%) along with its letter equivalent (i.e. 'C'). For the purposes of this program you can assume that A = 90-100, B = 80-89.99, C = 70-79.99, D = 65-69.99 and F is less than 65
  2. A company has determined that its annual profit is typically 23 percent of total sales. Write a program that asks the user to enter in the projected amount of total sales and then displays the profit that will be made from that amount.
  3. One acre of land is equivalent to 43,560 square feet. Write a program that asks the user to enter the total square feet in a tract of land and calculate the number of acres in that tract.
  4. A customer in a store is purchasing 5 items. Write a program that asks for the price of each item, and then displays the subtotal of the sale, the amount of sales tax, and the total. Assume the sales tax is 6 percent.
  5. Write a program to input a 2 digit integer, call it x, where the rightmost digit is nonzero. Compute the integer y which has the same digits as x, but in reverse order. Print out x, y and x+y. For example:
Please enter a two digit integer: 23
23 reversed is: 32
23 + 32 is 55
  1. Analyze the code below and identify any problems or issues that might exist. Offer suggestions on how to re-engineer the code to prevent these errors from occurring and/or rewrite the code so that it functions correctly. rate = str(input("How much do you make per hour? '))
hours = input("How many hours did you work this week? ")

if hours < 40:
 pay = rate * hours
if hours > 40
 pay = rate * 40
 ot_pay = (hours-40) ** (rate*1.5)

print ("Your total pay is, pay + ot_pay")
  1. Write a program that lets the user figure out how many items they can purchase at a local coffee shop. Begin by asking the user to enter in amount of money as a float. Then ask the user to select a product from a pre-determined list. Figure out how many items the user can purchase, noting that the coffee shop does not sell fractional amounts (i.e. you can't buy half a donut)
How much money do you have?: 10.00

What would you like to buy?
Donut (d) - $1.50
Coffee (c) - $1.00
Bagel (b) - $2.50
Scone (s) - $2.75

Enter your choice (d/c/b/s): d

You can purchase 6 donuts with $ 10.0 Note that you cannot assume that the user will enter a valid product (i.e. they could type in the string "donut" instead of the string "d"). In this case you will need to present the user with some kind of error (i.e. "Sorry, that's not a valid product") ' you do not need to re-prompt them (you can just end the program). Also, you can assume that the user will input valid floating-point numbers when prompted.
  1. Write a "calculator" program that asks the user for two numbers as well as an "operation code" ("a" for add, "s" for subtract, "d" for divide or "m" for multiply). Using the information provided perform the specified operation and print the result. Note that you cannot assume that the user will enter a valid operation code (i.e. they could type in the string "multiply" instead of the string "m"). In this case you will need to present the user with some kind of error (i.e. "Sorry, that's not a valid operation code") and exit the program. However, you can assume that the user will input valid floating-point numbers when prompted. Also note that dividing a number by 0 will result in a runtime error. Prevent this from happening in your program by providing special output in this case (i.e. 5.0 / 0.0 = undefined). Here is a sample running of the program:
Number 1: 2.0
Number 2: 3.0
Operation (a/s/d/m): add
Invalid operation! Try again.
Operation (a/s/d/m): a
2.0 + 3.0 = 5.0
  1. A small college has asked you to write a program for their admissions department to help them determine if a student should be accepted into their school. Write a program that uses the following criteria to determine whether a given applicant should be admitted:
    • Combined SAT score of 1600 or more
    • A high school GPA of 3.0 or higher
    • At least 3 extracurricular activities. This particular school places a heavy emphasis on extracurricular activities, so students with 5 or more activities only need a 1400 combined score on their SAT and a GPA of 2.8. Comment your code as necessary. You can assume that the user will enter floating-point values. Here is a sample running of your program.
Student name: Craig
Combined SAT Score: 1800
High school GPA: 3.2
# of extracurricular activities: 3
Craig should be admitted!

Student name: John
Combined SAT Score: 1500
High school GPA: 3.1
# of extracurricular activities: 7
John should be admitted!

Student name: Chris
Combined SAT Score: 1300
High school GPA: 2.9
# of extracurricular activities: 8
Chris should not be admitted.

Functions practice:

  1. Create a function that can accept two arguments: name and age, and print out their value in the format, "Bob: 22 years old"
  2. Write a function calculation() such that it can accept two numeric values as arguments and calculate the sum and difference of those values. It returns either the sum or difference, depending on the value of a fourth argument which is assumed to be either the string "sum" or "difference".
  3. Write a Python function to check whether a given number is in a given range - where the number, and range are supplied as arguments to the function and the function returns True or False
  4. Write a Python function that takes a number as a parameter and check the number is prime or not.