Unsigned char
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| − | + | '''unsigned char''' is the smallest unsigned integer type in C++, it often gets typedef-ed as "byte" (alternatively people use [[signed char]] for that reason) because it uses one byte of memory (depending upon what architecture defines it as, but no less than 8 bits). The range of values that can definitely be stored in this type is 0 – 255. | |
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Operation 255+1 will likely cause a "roll over" and the result will be 0, but it is unwise to count on that when writing multi-architecture code, as it is possible to define byte in a processor to be more than 8 bits. | Operation 255+1 will likely cause a "roll over" and the result will be 0, but it is unwise to count on that when writing multi-architecture code, as it is possible to define byte in a processor to be more than 8 bits. | ||
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==Other C++ datatypes of the same size== | ==Other C++ datatypes of the same size== | ||
Latest revision as of 11:30, 31 July 2023
unsigned char is the smallest unsigned integer type in C++, it often gets typedef-ed as "byte" (alternatively people use signed char for that reason) because it uses one byte of memory (depending upon what architecture defines it as, but no less than 8 bits). The range of values that can definitely be stored in this type is 0 – 255.
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | value |
|---|---|---|---|---|---|---|---|---|
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 128 |
| 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 127 |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 255 |
Operation 255+1 will likely cause a "roll over" and the result will be 0, but it is unwise to count on that when writing multi-architecture code, as it is possible to define byte in a processor to be more than 8 bits.
[edit] Other C++ datatypes of the same size
[edit] Other C++ data types storing unsigned integers
- unsigned short no less than 16 bits, no less than char
- unsigned (int) no less than 16 bits, no less than short
- unsigned long no less than 32 bits, no less than int
- unsigned long long no less than 64 bits, no less than long
