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> : คุณได้ 10.0 คะแนน (เต็ม 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();
    int i=0,d=1,c=1;
    double pi1 = 0, pi2 = 4.0;
    
    while (i < k) {
      pi1 += (double)c / d;
      c *= -1;
      d+=2;
      i++;
      }
    pi1 *= 4;
    c=2;d=3;i=0;
    while (i < k) {
      pi2 *= (double)c / d;
      if(i%2==0)c+=2;
      else d+=2;
      i++;
      }
    

    System.out.println("Pi = " + pi1);  // แสดงผลของสูตรแรก
    System.out.println("Pi = " + pi2);  // แสดงผลของสูตรที่สอง
  }

}

SM=1, CM=8, ST=11, KY=194, TR=60:00
ERR = 60:00 ;
ERR = 60:00 1021,;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;