Skip to main content

CS1 Python Subgoals

Section 7.3 Assessment: Writing Loops

Subgoals for Writing a Loop.

  1. Determine purpose of loop
    🔗
    1. Pick a loop structure (while, for, do_while)
      🔗
      🔗
    🔗
    🔗
  2. Define and initialize variables
    🔗
    🔗
  3. Determine termination condition
    🔗
    1. Invert termination condition to continuation condition
      🔗
      🔗
    🔗
    🔗
  4. Write the loop body
    🔗
    1. Update Loop Control Variable to reach termination
      🔗
      🔗
    🔗
    🔗
🔗

Exercises Exercises

    1.

    Q1: Given the following code segment:
    🔗
    x = 1
while ___:
    if x % 2 == 0:
        print(x)
    x = x + 2
    Consider the following conditions to replace ___ in the code segment:
    🔗
    1. x < 0
      🔗
      🔗
    2. x <= 1
      🔗
      🔗
    3. x < 10
      🔗
      🔗
    🔗
    For which of the conditions will nothing be printed?
    🔗
    🔗

    2.

    Q2: Given the following code segment which is intended to print the number of integers that evenly divide the integer input_val. (You may assume that input_val > 0.)
    🔗
    count = 0
input_val = int(input())
for k in range(1, input_val):
    if ___:
        count += 1;
print(count)
    Which of the following can be used to replace ___ so that the code will work as intended?
    🔗
    • input_val % k == 0
      🔗
    • k % input_val == 0
      🔗
    • input_val % k != 0
      🔗
    • input_val / k == 0
      🔗
    • k / input_val > 0
      🔗
    🔗

    3.

    Q3: Which of the following code segments will produce the output:
    🔗
    1 4 7 10 13 16 19
    🔗
    k = 1
while k < 20:
    if k % 3 == 1:
        print(k, end=" ")
    k = k + 3

    for k in range(1, 19):
    if k % 3 == 1:
        print(k, end=" ")

    k = 1
while k < 20:
    print(k, end=" ")
    k = k + 3
    🔗

    4.

    Q4: What is the maximum number of times “Hello” can be printed?
    🔗
    k = # a random number such that 1 <= k <= n 
for p in range(2, k):
    for r in range(1, k - 1):
        print("Hello")
    🔗

    5.

    Q5: Fill in the blanks in the following code to create a program that will print the prime numbers between 1 and 100 (inclusive). 
    for i in range(__A__, __B__):
    is_prime = True
    for j in range(__C__, __D__):
        if i % j == __E__:
            is_prime = False
    if is_prime:
        print(i, end=" ")
    🔗
    Blank A:
    🔗
    Blank B:
    🔗
    Blank C:
    🔗
    Blank D:
    🔗
    Blank E:
    🔗
    🔗
🔗
You have attempted 1 of 2 activities on this page.
🔗
PrevTopNext