package codewars;//https://www.codewars.com/kata/55830eec3e6b6c44ff000040/train/javaimport java.math.BigInteger;public class Oddity{    public static String oddity(BigInteger n){        BigInteger low = BigInteger.ONE;        final BigInteger TWO = new BigInteger("2");        BigInteger high = n;        while(low.compareTo(high) <= 0){            BigInteger mid = null;            if(BigInteger.ZERO.compareTo(low.add(high).mod(TWO)) == 0){                mid = low.add(high).divide(TWO);            }else{                mid = low.add(high).divide(TWO).add(BigInteger.ONE);            }                int temp = mid.multiply(mid).compareTo(n);            if(temp == 0){                return "odd";            }else if(temp < 0){                low = mid.add(BigInteger.ONE);            }else{                high = mid.substract(BigInteger.ONE);            }               }           return "even";     }    }

import static org.junit.Assert.assertEquals;import org.junit.Test;import java.math.BigInteger;public class OddityTest{    @Test        public void exampleTests(){        assertEquals("odd", Oddity.oddity(BigInteger.valueOf(4)));        assertEqulas("even", Oddity.oddity(BigInteger.valueOf(12)));    }    }