question: public void testFlipBitNegativeInside3 ( ) { String as = "-18446744073709551615" ; String res = "-18446744073709551611" ; int number = 2 ; BigInteger aNumber = new BigInteger ( as ) ; BigInteger result = aNumber . flipBit ( number ) ; assertEquals ( res , result . toString ( ) ) ; }
target:  flipBit(int n) inside a negative number with all ones in bit representation 