KwickClips C++ · 44 sec · free
What is the size of a union?
Short answer. The size of its largest member.
How many union members are valid at once?
One.
Structure vs union
| Point | struct | union |
|---|---|---|
| Memory | each member | shared |
| Size | sum | largest |
| Valid values | all | one |
Remember
| Union members share memory |
| Only one value at a time |
Same members, yet a union is smaller. How? Compare. Structure members each get memory. Union members share it. So a union is its largest member's size. One value is valid. Remember this. Union members share memory. One value at a time.
This clip is from the full lesson: Structures, Unions, Enumerations and typedef — 6 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: GSEB Std 10 Computer Studies, GSEB Std 10 Computer Studies, GSEB Std 10 Computer Studies, Programming All levels C
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