Unsigned meaning in c language

unsigned is a keyword that represents unsigned integers in C language. It has the following advantages: improve efficiency (avoiding storing sign bits); avoid overflow errors (only represent positive values); and simplify code (no need to process symbols).

What is unsigned in C?

In C language, unsigned is a keyword used to modify an integer variable or type, indicating that the variable or type represents an unsigned integer.

The meaning of unsigned integers

The difference between unsigned integers and signed integers is that:

• Range: Unsigned integers can only represent positive values ​​and zeros, while signed integers can represent positive values, negative values ​​and zeros.
• Binary bits: All binary bits of an unsigned integer are used to represent their size, while the highest bit of a signed integer (the leftmost bit) is used to represent a symbol (positive or negative).

Advantages of using unsigned

The main advantages of using unsigned to modify integer variables or types are:

• Improve efficiency: Unsigned integers are more efficient in storage and operation because they do not require storing sign bits.
• Avoid overflow errors: When the value of a signed integer exceeds its maximum or minimum value, it overflows, resulting in an error. Unsigned integers do not overflow, because they can only represent positive values.
• Simplified code: Using unsigned can avoid processing symbols, thus simplifying code.

Notes on using unsigned

The following points should be paid attention to when using unsigned :

• Only positive values ​​are expressed: an unsigned variable or type can only represent positive values ​​and zeros, and cannot represent negative values.
• Negative operation cannot be performed: Negative operation, such as subtraction or inverse, cannot be performed on unsigned variables or types.
• Unexpected results may occur: If you cast signed integers to unsigned type and try to perform negative operations on the result, you may get unexpected results.

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