One call inside another

One cloth bag holds the morning fares. Another holds the evening fares. One line finds which bag has the bigger total.

Press the button below. Watch each call turn into a number.

The rule

The list morning holds 8, 6, 10 and 6 rupees. The list evening holds 12, 8, 6 and 8.

total adds up a bag and hands back the sum. max takes two numbers and hands back the larger.

A call is a value. So a call can sit inside another line. The inside call runs first. It hands its value up. Only then does the outer line have what it needs.

`` max(total(morning), total(evening)) ``

1. total(morning) runs all the way through. It gives 8 + 6 + 10 + 6 = 30.
2. total(evening) runs. It gives 12 + 8 + 6 + 8 = 34.
3. max(30, 34) runs. It gives 34.

So the evening bag has the bigger total, 34.

Try the lab to finish this lesson.