View Compilation Error

0_0_5958187_3039\Main.java:10: cannot find symbol
symbol  : method valueOf(java.lang.String)
location: class java.math.BigInteger
			BigInteger x=BigInteger.valueOf(cin.nextLine());
			                       ^
0_0_5958187_3039\Main.java:11: cannot find symbol
symbol  : method valueOf(java.lang.String)
location: class java.math.BigInteger
			BigInteger y=BigInteger.valueOf(cin.nextLine());
			                       ^
2 errors