Use -- random number usage and probability of generation, random number Probability

Use -- random number usage and probability of generation, random number Probability

The Random class is used to generate Random numbers within a specified range. The constructor has two types of constructor without parameters and parameters. The constructor with parameters has the number of seeds.

Assume that the following r is a Random object

Random r = new Random ();

1. generate any integer

Int I = r. nextInt ();

2. generate an integer in the range [0, n] (two types)

Int I = r. nextInt (n + 1 );

N3 = Math. abs (r. nextInt () % (n + 1 ));

3. generate an integer in the [0, n) Interval

Int I = r. nextInt (n );

4. Generate decimal places in the range [0, 1.0)

Double d = r. nextDouble ();

5. Generate decimal places in the range [1, 2.5)

Double d = r. nextDouble () * 1.5 + 1;

It is worth noting that if the r constructor carries Parameters

Random r = new Random (n)

The n parameter is of the long type. It is called the number of seeds. a Random number is generated with the same number of seeds.

Test as shown in Figure

Therefore, you can use only one project.

In addition, Math also provides a function random () to generate a pseudo-random double value greater than or equal to 0.0 and less than 1.0.