Page 235 - Learn To Program With Scratch

9

L i S t S

The programs we’ve written so far have used ordinary

variables to store single pieces of data. Such variables
are not as useful, however, when you want to store a
bunch of values, such as your friends’ phone numbers,
names of books, or a month of temperature readings.

For example, if you wanted your program to remember the phone numbers
of 20 of your friends, you’d need 20 variables! Certainly, writing and main-
taining a program with 20 variables would be tedious. In this chapter, we’ll
explore another built-in data type, called a list, which offers a convenient
way to group related values. Here’s what we’ll cover:
• How to create and manipulate lists
• Initializing and accessing individual elements in a list
• Basic sorting and search techniques
• Using lists to create powerful applications

First, I’ll explain how to make lists in Scratch, demonstrate the com-
mands you can use with them, and show you how to populate lists with data

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