What is unsigned in computer programming

In computer programming, the term "unsigned" refers to a variable that can only hold positive numbers. "Signed" in computer code means that a variable can contain negative and positive values. This property applies to most numeric data types, including int, char, short, and long.

Unsigned variable integer type

The int of the unsigned variable type can contain zero and positive numbers, while the signed int can contain Negative numbers, zero and positive numbers.

In 32-bit integers, the range of unsigned integers is 0 to 232-1 = 0 to 4,294,967,295, which is approximately 4 billion. The signed version goes from -231-1 to 231, which is -2,147,483,648 to 2,147,483,647, or - 2 billion to 2 billion. The range is the same, but moved on the number line.

By default, the int type in C, c and c# is signed. If negative numbers are involved, the programmer must change to unsigned.

Unsigned characters

For characters with only 1 byte, the range of unsigned characters is 0 to 256, while the range of signed characters is -127 to 127 .

Independent type specifiers and other uses

Unsigned (and signed) can also be used as independent type specifiers, but if used individually, they default to int .

Objects of type long can be declared as signed long or unsigned long. Signed long is the same as long because signed is the default.

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