Java – which data type or data structure to choose to calculate the factorial of 100?

I want to write a program to evaluate the factorial of a given integer

The following basics I wrote the following code in Java:

long fact(int num){
if(num == 1)
 return 1;
else
 return num*fact(num-1);
}

But then I realized that for many integer inputs, the result may not be what I expected, so for the test, the input is 100

I doubt it's true because I get a result of "0" (the reason and result may be beyond the long-term range)

So I'm just curious and eager to know how to make my program suitable for input < = 150 I appreciate any effective solution in C programming language or Java

Solution

BigInteger is your class It can store integers of any size

static BigInteger fact(BigInteger num) {
        if (num.equals(BigInteger.ONE))
            return BigInteger.ONE;
        else
            return num.multiply(fact(num.subtract(BigInteger.ONE)));
    }