Lab2-Pi

JLab>java Selftest 

JLab> testPi : ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok ok  (10.0/10.0)
JLab> : -----------------------------
JLab> : ?????? 10.0 ????? (???? 10.0)
JLab> : -----------------------------
JLab> :<POINT>10.0</POINT> (<TOTAL>10.0</TOTAL> )
JLab>

import java.util.Scanner;

public class Pi {
  // pi1 = 4*(1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 + ...)
  // pi2 = 4*(2/3 * 4/3 * 4/5 * 6/5 * 6/7 * 8/7 * ...)
  public static void main(String[] args) {
    Scanner kb = new Scanner(System.in);
    System.out.print("k = ");
    int k = kb.nextInt();

    double pi1 = 0, pi2 = 1, x = 1;
    int m = 1;
    while (m <= k) {
      pi1 = pi1 + (x / (2 * m - 1));
      x = x * -1;
      m++;
    }
    pi1 = pi1 * 4;
    
    m = 1;
    while (m <= k) {
      if (m % 2 == 0) {
        pi2 = pi2 * ((m + 2.0) / (m + 1.0));
      } else {
        pi2 = pi2 * ((m + 1.0) / (m + 2.0));
      }
    m++;
    }
    pi2 = pi2 * 4;
    
    System.out.println("Pi = " + pi1);  // แสดงผลของสูตรแรก
    System.out.println("Pi = " + pi2);  // แสดงผลของสูตรที่สอง
  }

}

SM=0, CM=2, ST=3, KY=223, TR=60:00
ERR = 60:00 ;
ERR = 60:00 ;