stl bitset

#include <iostream>
#include <bitset>

using namespace std;

int main()
{
  bitset<12>mask(127);
  bitset<12>haha(128);
  
  cout << "mask= " << mask << endl;
  cout << mask.to_ulong() << endl;
  cout << "haha= " << haha << endl;
  haha |= mask;
  cout << "haha|mask= " << haha << endl;
  haha &= mask;
  cout << "haha&mask= " << haha << endl;
  haha ^= mask;
  cout << "haha^mask= " << haha << endl;



  return 0;
}


 

Tencent:/data/kenthy/stl/bitset # ./bitset       
mask= 000001111111
127
haha= 000010000000
haha|mask= 000011111111
haha&mask= 000001111111
haha^mask= 000000000000

很奇怪的是,求| ^ &的时候,需要bitset的位数是一样的....