signed and unsigned in c
Signed and Unsigned in C
In the C programming language, the terms "signed" and "unsigned" are used to describe integer data types. These terms indicate whether the data type can represent both positive and negative values (signed) or only non-negative values (unsigned). Let's explore the differences between signed and unsigned in C.
Signed Integers
A signed integer can represent both positive and negative values. It uses a sign bit to determine the sign of the value. The sign bit is typically the most significant bit (MSB) in the binary representation of the number.
For example, a signed 8-bit integer can represent values from -128 to 127. The range of values that can be represented by a signed integer depends on the number of bits allocated for the data type.
Unsigned Integers
An unsigned integer, on the other hand, can only represent non-negative values. It does not use a sign bit and can represent a larger range of positive values compared to signed integers of the same size.
For example, an unsigned 8-bit integer can represent values from 0 to 255. The absence of a sign bit allows the entire range of bits to be used for positive values.
Conversion between Signed and Unsigned
When converting a signed integer to an unsigned integer, the value remains the same, but the interpretation changes. The sign bit is not preserved, and the value is treated as a positive number.
When converting an unsigned integer to a signed integer, the value is preserved if it falls within the range of the signed integer. However, if the value exceeds the range of the signed integer, the behavior is implementation-defined.
Conclusion
In summary, the terms "signed" and "unsigned" in C refer to the ability of an integer data type to represent both positive and negative values or only non-negative values, respectively. Signed integers use a sign bit to determine the sign, while unsigned integers do not have a sign bit. Conversion between signed and unsigned integers can result in different interpretations of the same value.