Factorial java return 0

Question

I made a simple function to calculate the factorial of a number but from number 34 returns 0 . It should be from number 51 .

   public class Métodos {
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Answer 1

1- I'm a native Portuguese speaker and please follow my advice: "Write code in English." It is easier for the world to read and when you get to conventions your methods will have names like getSomething() or setSomething(something).

2- About your problem. Try:

for (int i = 0 ; i < 60; i++){
    System.out.println(i + " " + factorial(i));
}

You will see that around 12 you start getting strange values because an int in java is limited to 2^31-1 and you are getting overflows: http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html

You can try a long. But that will also overflow long before 51.

You will have to use the BigInteger class that handles arbitrary values.

public static BigInteger factorial(BigInteger number) {
    if ((number.compareTo(BigInteger.ZERO) == 0)
            || (number.compareTo(BigInteger.ONE) == 0)) {
        return BigInteger.ONE;
    } else {
        return number.multiply(factorial(number.subtract(BigInteger.ONE)));
    }
}