Structure & Union Questions and Answers
Structure & Union Questions with Answers are key topics in C programming questions and answers sections of competitive exams and technical interviews. These concepts allow efficient memory usage and data management, making them essential for understanding advanced C applications. Commonly featured in TCS, Infosys, and Tech Mahindra placement tests, questions on structure and union test your ability to differentiate between memory allocation, member access, and implementation. Practicing C programming MCQs with explanations improves conceptual clarity and debugging skills. Start your preparation with our curated C Structure & Union MCQs and download free PDFs for revision.
Structure & Union
Showing 10 of
95 questions
61. Find the output union xxx { int x; float y; char z; }; void main ( ) { union xxx abc; abc.x=10; abc.y=3.14; printf("%d", abc.x);
- 10
- 3.14
- Garbage value
- Compilation error
62. Find the output union abc { int a; long b; }; void main ( ) { union abc x; x. b=10; printf("%1d %d", x.b); }
- 10 10
- 10 Garbage value
- Garbage value 10
- Compilation error
63. Which of the following is flse regarding bit fields?
- Bit fields may share a storage unit with other structure members
- Bit fields must entirely reside in a storage unit of its appropriate type.
- Bit fields only applicable to unsigned integral but not signed integral.
- Bit fields are used to construct the protocol header fields.
64. Which of the following is best suited for memory optimization
- Union
- Self referential structure
- Array
- Linked list
65. Very first member of union is known as
- smart member
- Lical member
- Data member
- Active member
66. Union is
- A special jtype of structure
- A pointerdata type
- A function data type
- Not a data type
67. Find the output union xyz float f; int i; } xx=5.0; void main ( ) { printf ('%f %d", xx.f, xx.i); }
- 5.0000 0
- 5.0000 Garbage
- Garbage garbage
- Compilation Error
68. Which of the following statements true regarding UNION ? I. Self-referential structure may be used as member of union. II. Niested union is also possible. III. ONe member of a union active at a time. IV. Only active member can be initialized.
- III & IV
- II, III & IV
- I, II & III
- All of these
69. Find the output union usa { unsigned int x[2]; char ch[4]; } canada; void main ( ) { strcpy (canada.ch, "xyz")); printf('%s%d", canada. ch, canada.x[1]); }
- Error: Library function not allowed initializing union member.
- xyz 120
- xyz 121
- xyz 122
70. The main advantage of union over structure is
- Memory mapping
- Memory utilization
- Memory optimization
- Memory leak