public void And(BitSet bs) {
if (bs == null) {
throw new ArgumentNullException("bs");
}
if (this == bs) {
return;
}
while (this._wordsInUse > bs._wordsInUse) {
this._bits[--this._wordsInUse] = 0;
}
for (Int32 i = 0; i < this._wordsInUse; i++) {
this._bits[i] &= bs._bits[i];
}
this.RecalculateWordsInUse();
this.CheckInvariants();
}