Pseudocode Mapping

Throughout these lessons, you've been seeing flowcharts and pseudocode side by side. Now it's time to make the connection crystal clear. Every flowchart shape maps to a specific pseudocode pattern, and every line of pseudocode can be drawn as a flowchart shape. Once you learn these mappings, you can translate freely between the two.

The Mapping Table

Here's the master reference. Each flowchart shape has a matching pseudocode pattern:

Pseudocode Keywords

Here are the pseudocode keywords you've learned in these lessons. They're not tied to any real programming language — they're just clear English words that describe what's happening.

Putting It All Together

Here's a complete program that uses everything you've learned: variables, input, output, an if-else statement, and a while loop. It's a guessing game — the computer picks a number and you keep guessing until you get it right.

Step through the flowchart and pseudocode together. Notice how each shape in the flowchart corresponds to exactly one line (or block) in the pseudocode.

BEGIN
  SET secret = 7
  SET guess = 0
  WHILE guess != secret
    OUTPUT "Enter your guess:"
    INPUT guess
    IF guess < secret THEN
      OUTPUT "Too low!"
    ELSE
      OUTPUT "Too high!"
    END IF
  END WHILE
  OUTPUT "Correct! You got it!"
END

This program combines variables (secret, guess), input/output (asking for guesses, showing hints), a while loop (keep guessing until correct), and an if-else (is the guess too low or too high?). Every concept from the previous lessons works together!

Translation Rules: Flowchart to Pseudocode

When you want to convert a flowchart into pseudocode, follow these steps:

1. Start at the top — write BEGIN.
2. Follow the arrows — each shape becomes one line (or block) of pseudocode.
3. Rectangles become assignment statements: SET x = value
4. Parallelograms become INPUT or OUTPUT statements.
5. Diamonds become IF, WHILE, or FOR EACH — look at whether the No arrow goes forward (it's an if) or backward (it's a loop).
6. Indent everything inside an if-block or loop body.
7. End at the bottom — write END.

Translation Rules: Pseudocode to Flowchart

Going the other direction — pseudocode to flowchart — use these rules:

1. BEGIN and END become oval shapes at the top and bottom.
2. SET / assignment statements become rectangles.
3. INPUT / OUTPUT become parallelograms.
4. IF ... THEN becomes a diamond with Yes and No arrows going forward.
5. WHILE ... becomes a diamond with the Yes arrow going to the loop body and the No arrow going forward. At the end of the loop body, draw an arrow back up to the diamond.
6. FOR EACH ... IN ... works the same way as while — diamond with a back arrow.
7. Connect everything with arrows, flowing top to bottom.

Quick Reference Card

Here's a cheat sheet showing each structure as both a mini flowchart and pseudocode:

IF condition THEN
  do something
END IF

IF condition THEN
  do this
ELSE
  do that
END IF

WHILE condition
  do something
  update variable
END WHILE

FOR EACH item IN list
  do something with item
END FOR EACH