In C#, the ~ operator is a unary bitwise NOT operator. It inverts each bit of its integer operand, effectively producing the two’s complement representation of the number, which results in the negative of that number. Here are some key points about the ~ operator:
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Bitwise Inversion: The ~ operator flips all bits of the operand. For example, applying ~ to 5 (binary 0101) results in –6 (binary 1010).
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Integral Types Only: This operator is only applicable to integral types such as int, long, short, and byte. Using it with non-integral types like floating-point numbers will result in a compile-time error.
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Two’s Complement Representation: The result of the ~ operator is based on two’s complement notation, which means that flipping all bits of a positive number yields its negative counterpart, and vice versa.
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Example Behavior:
- int x = 5; results in ~x == –6.
- int y = –1; results in ~y == 0.
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byte z = 1; results in ~z == 254 (but interpreted as a signed byte, it would be –1).
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Edge Cases:
- Applying ~ to zero ( int x = 0;) results in –1.
- Larger data types like long also follow the same inversion principle.
Understanding the behavior of the ~ operator is crucial for manipulating bits directly, especially in scenarios requiring bitwise operations or specific algorithms that rely on bit inversion.