simple-type-specifier := unsigned

The unsigned type specifier can be used with any integral type to make the type unsigned. Unsigned integer arithmetic is always performed modulo 2ⁿ, in which n is the number of bits in the value representation of the integer. When used alone, unsigned means unsigned int.

Example

char c;
if (isalpha(static_cast<unsigned char>(c))
  handle_alpha(c);

See Also

char, int, long, short, signed, type, Chapter 2