Structure vs union comparison in C++ - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a structure named MyStruct.

C++

struct [1] {
    int a;
    float b;
};

Drag options to blanks, or click blank then click option'

AMyStruct

BData

CMyUnion

DStruct1

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'union' instead of 'struct' as the name.

Choosing a name that doesn't match the declaration.

The keyword struct is followed by the structure name. Here, MyStruct is the correct name.

2fill in blank

medium

Complete the code to declare a union named MyUnion.

C++

union [1] {
    int x;
    double y;
};

Drag options to blanks, or click blank then click option'

AMyStruct

BMyUnion

CDataUnion

DUnion1

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'struct' instead of 'union' as the name.

Choosing a name that doesn't match the declaration.

The keyword union is followed by the union name. Here, MyUnion is the correct name.

3fill in blank

hard

Fix the error in the code to correctly access the union member.

C++

MyUnion u;
u.[1] = 10;

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Ab

Ba

Cx

Dy

Attempts:

3 left

💡 Hint

Common Mistakes

Using a member name that does not exist in the union.

Assigning a value to a member of a different type.

The union MyUnion has members x and y. To assign an integer value, use x.

4fill in blank

hard

Fill both blanks to create a structure and access its member.

C++

struct [1] {
    int age;
};

[2] person;
person.age = 25;

Drag options to blanks, or click blank then click option'

APerson

BMyStruct

DMyUnion

Attempts:

3 left

💡 Hint

Common Mistakes

Using different names for the structure and variable type.

Confusing structure and union names.

The structure name MyStruct (B) goes in BLANK_1. The declaration MyStruct person; uses the same type (B) in BLANK_2 to match the structure name.

5fill in blank

hard

Fill all three blanks to create a union, assign a value, and print the size.

C++

union [1] {
    int i;
    char c;
};

[2] u;
u.i = 100;

std::cout << sizeof([3]) << std::endl;

Drag options to blanks, or click blank then click option'

ADataUnion

Bu

DMyUnion

Attempts:

3 left

💡 Hint

Common Mistakes

Using inconsistent names for union and variable.

Using variable name instead of type in sizeof.

The union is named MyUnion. The variable u is declared as type MyUnion. The sizeof operator is used on the union type MyUnion to print its size.