Structure vs union comparison - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a structure named Person.

C

struct Person {
    char name[50];
    int age;
    float height;
};

struct [1] person1;

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

AStruct

BUnion

CData

DPerson

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Union' or 'Struct' as a type name instead of the declared structure name.

Forgetting to use the structure name after 'struct'.

The keyword Person is the name of the structure type declared earlier. We use it to declare a variable of that type.

2fill in blank

medium

Complete the code to declare a union named Data.

C

union [1] {
    int i;
    float f;
    char str[20];
};

union Data data1;

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

APerson

BData

CUnion

DStruct

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Union' or 'Struct' as the union name.

Using the wrong name that does not match the union declaration.

The union is named Data. We use this name to declare variables of this union type.

3fill in blank

hard

Fix the error in accessing the union member to assign a value.

C

union Data data1;
data1.[1] = 10;

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

Ai

Bheight

Cname

Dage

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to access members that belong to a structure but not the union.

Using member names that do not exist in the union.

The union Data has a member named i for integer values. We assign 10 to data1.i.

4fill in blank

hard

Fill both blanks to create a structure and a union variable.

C

struct [1] person2;
union [2] data2;

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

APerson

BData

CEmployee

DInfo

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up structure and union names.

Using names not declared earlier.

The structure is named Person and the union is named Data. We use these names to declare variables.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension-like code in C style (simulate with comments) comparing sizes of structure and union.

C

/* Size of struct Person: sizeof(struct [1]) */
/* Size of union Data: sizeof(union [2]) */
/* The size difference is because [3] */

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

APerson

BData

Cunion shares memory among members

Dstruct shares memory among members

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing structure and union names.

Incorrect explanation about memory sharing.

The size of a structure is the sum of all members, so we use Person. The union size is the size of its largest member, so Data. The union shares memory among members, which is why its size is smaller.