Each bit represents either the value zero (reset) or one (set)
.To
toggle
a bit is to change the value zero to one, or the value one to
zero
.Each bit has a non-negative position 
pos.When converting
between an object of class
bitset<N>
and a value of some
integral type, bit position 
pos corresponds to the
bit value
1 << pos.The integral value corresponding to two
or more bits is the sum of their bit values
.