Exception in thread "main" java.lang.NumberFormatException: Zero length BigInteger

This exception occurs when we try to create a BigInteger object with a zero-length string as input. BigInteger is a class in Java that allows us to perform arithmetic operations with arbitrarily large integers.

Consider the following example:

String str = "";
BigInteger bigInt = new BigInteger(str);

In this example, we are trying to create a BigInteger object with an empty string. Since the string is empty, the BigInteger constructor throws a NumberFormatException with the message "Zero length BigInteger".

To fix this error, we need to ensure that the string passed to the BigInteger constructor is not empty. We can add a check to verify that the string is not empty before creating the BigInteger object:

String str = "12345";
if (!str.isEmpty()) {
    BigInteger bigInt = new BigInteger(str);
}

In this modified example, we only create the BigInteger object if the string is not empty.