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c++binarybitbitset

How to get bitset OR with different bitset sizes

When I use,

  std::bitset<5> op1 (std::string("01001"));
  std::bitset<5> op2 (std::string("10011"));

  std::cout << (op1|=op2) << std::endl;

everything is fine obviously.

But my question is, how can I use OR operation using two different sized 'std::bitset's? Such as,

  std::bitset<11> op1 (std::string("101110011"));
  std::bitset<5> op2 (std::string("01001"));

  std::cout << (op1|=op2) << std::endl;

I can't compile this code in VS 2012. What have I missed here? Can't I use different sized bitsets for OR operations (and XOR as well)? Is this a platform specific problem?

Solution

  • The interface doesn't support this directly. You could construct a temporary bitset instead:

    // assuming op1 is larger
op1 |= std::bitset<op1.size()>(op2.to_ullong())

    If the larger bitset's value wouldn't fit in a unsigned long long, youl could call to_string instead.