Bitwise operations: Difference between revisions
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std::cout << "a xor b: " << (a ^ b) << '\n'; |
std::cout << "a xor b: " << (a ^ b) << '\n'; |
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std::cout << "not a: " << ~a << '\n'; |
std::cout << "not a: " << ~a << '\n'; |
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// Note: the C/C++ shift operators are not guaranteed to work if the shift count (that is, b) |
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// is negative, or is greater or equal to the number of bits in the integer being shifted. |
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std::cout << "a shl b: " << (a << b) << '\n'; // Note: "<<" is used both for output and for left shift |
std::cout << "a shl b: " << (a << b) << '\n'; // Note: "<<" is used both for output and for left shift |
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std::cout << "a shr b: " << (a >> b) << '\n'; // typically arithmetic right shift, but not guaranteed |
std::cout << "a shr b: " << (a >> b) << '\n'; // typically arithmetic right shift, but not guaranteed |
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unsigned int |
unsigned int ua = a; |
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std::cout << " |
std::cout << "a lsr b: " << (ua >> b) << '\n'; // logical right shift (guaranteed) |
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// there are no rotation operators in C++ |
// there are no rotation operators in C++, but as of c++20 there is a standard-library rotate function. |
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// The rotate function works for all rotation amounts, but the integer being rotated must always be an |
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// unsigned integer. |
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std::cout << "a rol b: " << std::rotl(ua, b) << '\n'; |
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std::cout << "a ror b: " << std::rotr(ua, b) << '\n'; |
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}</lang> |
}</lang> |
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