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;
    
    for (double m = 1, c = 1; m <= k; m++) {
      pi1 += (c / (2*m - 1));
      c *= -1;
    }
    pi1 = 4 * pi1;
    
    for (double a = 2, b = 3, m = 1; m <= k; m++, a++, b++) {
      if (m % 2 == 1) pi2 *= a / b;
      if (m % 2 == 0) pi2 *= (a + 1) / (b - 1);
      }
    pi2 *= 4;

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

}

SM=0, CM=8, ST=18, KY=263, TR=60:00
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;
ERR = 60:00 ;