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c++bitwise-operatorsbitwise-and

Use bitwise AND on an int in C++

My question is simple: how do I perform a bitwise AND on an int in C++?

#include <iostream>

int main() {
    unsigned int foo = 3;
    unsigned int bar = 6;
    std::cout << foo & bar;
    return 0;
}

Instead of outputting 2, it prints 3.

When I do any other bitwise operation, it also just prints the first variable.

How do I get it to do the operation?

Solution

  • You need to add parentheses around your foo & bar because the & operator has a lower precedence than the shift << operator.

    std::cout << (foo & bar);

    As a side note, I am surprised that the code compiles without the parentheses. Bonus: the doc for operator precedence rules on cppreference