Week 8: Conditions

A condition lets a program choose a path based on a question. In C, if asks the question. When the condition is true, the block after it runs. When it is false, the else block runs instead. Conditions use symbols such as ==, < and >. This week you learn to type four symbols on the US English layout, including the colon.

What you will learn

On the US English layout:

• :: the ; key with Shift. Press Shift with the opposite pinky, and press the ; key with your right pinky.
• <: the , key with Shift. Press Shift with the opposite pinky, and press the , key with your right middle finger.
• >: the . key with Shift. Press Shift with the opposite pinky, and press the . key with your right ring finger.
• =: the = key, with your right pinky.

Two short examples: if (score > 10) asks whether the score is above 10, and else covers the case when it is not. A label such as case 1: also ends with a colon.

Technique tips

• Think of if and else as a pair. Show which block belongs to which condition by indenting the lines inside each block.
• When you check for equality, type == rather than a single =. One equals sign stores a value, so it does not compare anything.
• Enter gives you the right indentation automatically. Check that else lines up with its if, but do not add extra spaces by hand.
• Look at the screen to confirm the colon, < and > landed correctly. Verify the symbols from the text, not from your hands.

Lessons

1. Lesson 1, learn (10 to 15 minutes): Watch the four symbols on the keyboard demo. Notice which finger holds Shift, then type each symbol five times.
2. Lesson 2, practice (10 to 15 minutes): Type short conditions with if and else, such as if (score > 10). Check that every if line has its parentheses complete.
3. Lesson 3, review (10 to 15 minutes): Take the two-minute test with condition lines. Save your result and practice the symbols you got wrong.

This week’s goal

This week’s target is 17 WPM and 92% accuracy. Finishing the week’s lessons earns you 1 star. Reach 92% accuracy for 2 stars, and also reach 17 WPM for 3 stars. A wrong symbol in a condition sends the program down the wrong path, so focus on accuracy first.