Math.random () follows which algorithms

Question

We use the method math.random()to generate random numbers. but I doubted this method. math.random () - which algorithms will fall to generate random numbers. Is there any other random number generated algorithm?

I am trying to execute this code, but I think it is inefficient for generating random code:

for (int i = 0; i < N; i++) {
     int sd = i + (int) (Math.random() * (N-i));

     String t = one[r];
     one[r] = one[i];
     one[i] = t;
 }

Is there a better random number generation algorithm?

Answer 1

Use java.util.RandomAPI

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Answer 2

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Answer 3

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String[] words = ...
Collections.shuffle(Arrays.asList(words));

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Random rand = new Random();
for (int i = words.length - 1; i > 0; i--) {
     int sd = rand.nextInt(i+1); // random number between 0 and i inclusive

     String t = words[r];
     words[r] = words[i];
     words[i] = t;
}

Answer 4

Java API .

java.lang.Math.random()

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private static Random randomNumberGenerator;

private static synchronized void initRNG() {
    if (randomNumberGenerator == null)
        randomNumberGenerator = new Random();
}

public static double random() {
    if (randomNumberGenerator == null) initRNG();
    return randomNumberGenerator.nextDouble();
}

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Answer 5

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2: Java Collection.shuffle()

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