how to input a BigInteger type in java
Make sure you prepare to catch an exception from the BigInteger - if the scanner fails to find a string you might get a BigInteger with non integer characters and it'll throw an exception.
Scanner scanner = new Scanner(fileOrOther);
try{
BigInteger bigint = scanner.nextBigInteger();
} catch(NumberFormatException ex) {
//handle Code here
}
Scanner sc = new Scanner(System.in);
BigInteger b = new BigInteger(sc.next());
There is also:
BigInteger b = sc.nextBigInteger();
How about
Scanner.nextBigInteger()
But I have to recommend that you read the documentation rather than ask this question. You harm yourself by not researching.
Scanner sc = new Scanner(System.in);
BigInteger bi = sc.nextBigInteger();
Reference: Scanner#nextBigInteger