如何以INT_MAX模数得到结果？

Question

If I try to apply: Integer.valueOf(String.valueOf(Integer.MAX_VALUE) + "9");
I get a NumberFormatException .

But I need to get the remainder modulo Integer.MAX_VALUE from the String representation.

How can I achieve that?

UPD: Integer.valueOf(String.valueOf(Integer.MAX_VALUE) + "9"); is just an example. The string can potentially have the value even more than max of Long.

Answer 1

You are looking for BigInteger . This allows math using very large numbers.

The following will allow you to do modulo with very large numbers:

BigInteger number = new BigInteger(myValueAsString);
BigInteger intMax = BigInteger.valueOf(Integer.MAX_VALUE);
BigInteger remainder = number.remainder(intMax);

Answer 2

To hold large number of input you can try BigInteger class. create one object that will hold your String input and modulo it with second BigInteger class object that will hold MAX_VALUE of integer.

You can write code as :

        BigInteger bigInteger = new BigInteger(str);
        bigInteger  = bigInteger.remainder(new BigInteger(String.valueOf(Integer.MAX_VALUE)));
        System.out.println(bigInteger);

Answer 3

try this

int i = (int)Long.parseLong(String.valueOf(Integer.MAX_VALUE) + "9");

note: I would use (Integer.MAX_VALUE + "9")

Answer 4

你也可以这样试试：

    System.out.println(Long.valueOf(String.valueOf(Integer.MAX_VALUE + "9")) % 5);

Answer 5

use

BigDecimal bd = new BigDecimal(str);

try the following code

int i = Integer.MAX_VALUE ;
System.out.println(i+1);