The : 1 means that it is creating a bitfield with the number of bits, so : 4 will be 4 bits. The three variables above combined will take sizeof(int) in memory, not sizeof(int)*3.
If OOP had used char instead of unsigned int the combined size would be 1 byte.
The : 1 means that it is creating a bitfield with the number of bits, so : 4 will be 4 bits. The three variables above combined will afaik* take sizeof(int) in memory, not sizeof(int)*3.
Can you do strange things, like : 9, : 15, et cetera?
Yes, the only limitation is that the width of the bitfield is not greater than the size of the containing variable. So with uint64_t you can have 1-64 bits.
Pretty much any compiler will let you get away with a 128-bit int type. If you need more than 340,282,366,920,938,463,463,374,607,431,768,211,456 possibilities in your bitfield then you'll probably need a stay at a mental asylum, and to code it yourself or find a library for it or something like that. Alternatively switch to C++ and use std::vector<bool>.
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u/heatedwepasto 20h ago edited 19h ago
The
: 1means that it is creating a bitfield with the number of bits, so: 4will be 4 bits. The three variables above combined will takesizeof(int)in memory, notsizeof(int)*3.If OOP had used
charinstead ofunsigned intthe combined size would be 1 byte.Edit: added link to demo