Union basics in C++ - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a union named Data.

C++

union [1] {
    int i;
    float f;
};

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AMyUnion

Bdata

CData

DValue

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase or different names like 'data' or 'MyUnion'.

Forgetting to write the union name after the keyword.

The union is declared with the name Data as required.

2fill in blank

medium

Complete the code to create a variable named d of the union Data.

C++

union Data d[1];

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A;

B()

C{}

D[]

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses or braces instead of a semicolon.

Omitting the semicolon at the end.

In C++, variables are declared with a semicolon ; at the end.

3fill in blank

hard

Fix the error in assigning the integer 10 to the union variable d.

C++

d.[1] = 10;

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Af

Bi

Cvalue

Ddata

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning to the float member f instead of i.

Using names not declared in the union.

The union has an integer member named i. Assigning to d.i stores the integer 10.

4fill in blank

hard

Fill both blanks to declare a union named Value with a char and a double member.

C++

union [1] {
    [2] c;
    double d;
};

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AValue

Bint

Cchar

Dfloat

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong union names like 'value' or 'Val'.

Using wrong types like 'int' or 'float' for the char member.

The union is named Value. It has a char member named c and a double member named d.

5fill in blank

hard

Fill all three blanks to create a union named Data with an int member i, a float member f, and assign 3.14 to f.

C++

union [1] {
    int [2];
    float f;
};

[1] d;
d.[3] = 3.14f;

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

AData

Bi

Cf

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing member names or union names.

Assigning a float value to the int member.

The union is named Data. It has an int member i and a float member f. The variable d is of type Data. The assignment d.f = 3.14f; sets the float member.