Pseudocode for planning in Intro to Computing - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Pseudocode Purpose

What is the main purpose of writing pseudocode before coding?

A To plan the steps of a program in simple language without worrying about syntax

B To create a detailed, executable program that runs on a computer

C To write the final version of the program in a specific programming language

D To test the program's performance and speed

💡 Hint

Think about how pseudocode helps programmers think through problems.

Pseudocode is used to plan the logic of a program in plain language. It helps programmers organize their thoughts before writing actual code.

❓ trace

intermediate

Tracing Pseudocode Execution

Given the following pseudocode, what will be the final value of total?

SET total TO 0
FOR each number FROM 1 TO 4
  ADD number TO total
END FOR

A 10

B 24

C 4

D 0

💡 Hint

Sum the numbers 1 + 2 + 3 + 4 step by step.

The loop adds 1 + 2 + 3 + 4 to total, which equals 10.

❓ Comparison

advanced

Comparing Pseudocode and Flowchart

Which statement best describes the difference between pseudocode and a flowchart?

A Flowcharts are faster to write than pseudocode.

B Pseudocode uses pictures to show steps; flowcharts use words only.

C Pseudocode is written in plain text; flowcharts use symbols and arrows to show flow.

D Flowcharts are only used for hardware design; pseudocode is for software.

💡 Hint

Think about how each method represents the steps of a program.

Pseudocode is text-based and describes steps in words. Flowcharts use shapes and arrows to visually represent the flow of steps.

❓ identification

advanced

Identifying Errors in Pseudocode

Which option shows pseudocode with a logical error?

Option A:
SET count TO 5
WHILE count > 0
  PRINT count
  DECREMENT count BY 1
END WHILE

Option B:
SET count TO 0
WHILE count < 5
  PRINT count
END WHILE

Option C:
SET total TO 0
FOR i FROM 1 TO 3
  ADD i TO total
END FOR

Option D:
SET x TO 10
IF x > 5 THEN
  PRINT "High"
END IF

A Option A has a logical error because it never stops.

B Option D has a logical error because the condition is always false.

C Option C has a logical error because the loop runs backwards.

D Option B has a logical error because count is never changed inside the loop.

💡 Hint

Look for loops that might never end.

Option D's loop never changes count, so it runs forever, causing an infinite loop.

🚀 Application

expert

Planning with Pseudocode for a Real-World Task

You want to write pseudocode to plan a program that checks if a number is prime. Which pseudocode snippet correctly plans this task?

A

SET number TO input
FOR i FROM 2 TO number
  IF number MOD i EQUALS 0 THEN
    PRINT "Prime"
  ELSE
    PRINT "Not prime"
  END IF
END FOR

B

SET number TO input
FOR i FROM 2 TO number-1
  IF number MOD i EQUALS 0 THEN
    PRINT "Not prime"
    STOP
  END IF
END FOR
PRINT "Prime"

C

SET number TO input
IF number MOD 2 EQUALS 0 THEN
  PRINT "Prime"
ELSE
  PRINT "Not prime"
END IF

D

SET number TO input
FOR i FROM 1 TO number
  PRINT i
END FOR
PRINT "Prime check complete"

💡 Hint

Think about how to test divisibility to confirm if a number is prime.

Option B correctly checks divisibility from 2 up to number-1 and stops if a divisor is found, printing "Not prime"; otherwise, it prints "Prime".