Тест: Dairy Purchase Data Processing Course — 3 въпроса

1. What is the main purpose of declaring and initializing a variable before using it in PSeInt?

A. To make the program run faster by skipping type checks

B. To reserve memory and give the variable a known starting value

C. To allow the variable to change type later in the program

D. To print the variable automatically on the screen

Answer: (B)

Обяснение

Declaration tells PSeInt the data type and reserves memory, while initialization gives the variable a defined starting value. Without initialization, the variable may contain an unusable or unpredictable value.

2. Why is it important to declare variables before using them in PSeInt, and what is the purpose of initializing variables after declaration?

A. Variables do not need declaration if they are only used once and initializing is only necessary for constants.

B. Declaring variables reserves memory and initializing sets a known starting value to prevent working with random data.

C. Declarations are optional, but initialization is required for the program to run correctly.

D. Declaration assigns a default value automatically, while initialization allows custom starting values.

Answer: (B)

Обяснение

Declaring variables in PSeInt reserves the necessary memory space, while initialization assigns a known value to prevent the program from using garbage data. This ensures reliable program behavior.

3. How are a vector and a matrix distinguished in this PSeInt program?

A. A vector cannot be accessed by index

B. A vector is always smaller than a matrix

C. A vector uses one index, while a matrix uses two indices

D. A vector stores only text, while a matrix stores only numbers

Answer: (C)

Обяснение

A vector is a one-dimensional structure accessed with one index, such as names[i]. A matrix uses two indices, such as precios[i, j], to represent team and provider.