3.7. Walking through Assignment more Generally¶
Let’s explore assignment in general. Try tracing this example.
The sequence of statements in a program is very important. Assignment doesn’t create some kind of relationship between the names, like in mathematics. The variable
a might equal
12 at one point, and
15 at another. An assignment statement is an action that occurs once, and then is over with.
We can see values (including the values for named variables) by printing them. It’s a useful way to see what’s going on inside a program. Try running this example where we’re having the computer calculate the number of days in three weeks:
The following program should figure out the cost per person for a dinner including the tip. But the blocks have been mixed up. Drag the blocks from the left and put them in the correct order on the right. Click the <i>Check Me</i> button to check your solution.</p>
10 people went to a restaurant for dinner. Each guest ate 1 appetizer and 1 entree. The whole party shared 1 dessert. Write the code to calculate and print the total bill if each appetizer costs $2.00, each entree costs $9.89, and dessert costs $7.99. It should print 126.89.
Create variables to hold each value. Calculate
(appetizer + entree) * numPeople + dessert. Be sure to print the result.
Discuss topics in this section with classmates.