PI

Main.java

import java.util.*;
import java.lang.*;
import java.io.*;
class Main{
	public static double PI = 3; //it is aproximally value
	public static void main (String[] args) throws java.lang.Exception{
        int n = 2;
        for (int i = 0; i < 500; i++) {
            PI += (i % 2 == 0 ? 1 : -1) * 4.0 / (n * (n + 1) * (n + 2));
            n += 2;
        }
        System.out.println(PI); }
}