pi.java

小程序

package mypackage;



public class Pi {
  public static void main(String[] args) {
          int ARRSIZE=103, DISPCNT=100; //定义数组大小，显示位数
       int [] x=  new int [ARRSIZE];//x[0] x[1] . x[2] x[3] x[4] .... x[ARRSIZE-1]
      int [] z = new int [ARRSIZE];
       int a=1, b=3, c, d,   Cnt=0;
        x[1] = 2;
       z[1] = 2;

       while( (++Cnt<20000))
       { d = 0;
         for(int i=ARRSIZE-1; i>0; i--)//z*=a;
         {
           c = z[i]*a + d;
           z[i] = c%10;
           d = c / 10;
         }

         d = 0;
         for(int i=0; i<ARRSIZE; i++)//z/=b;
         {
           c = z[i]+d*10;
           z[i] = c/b;
           d = c % b;
         }
      for(int i=ARRSIZE-1; i>0; i--)//x+=z;
         {
           c = x[i] + z[i];
           x[i] = c%10;
           x[i-1] += c/10;
          }
         a++;
         b+=2;
       }System.out .print("pi="+x[0]+(x[1])+".") ;

       for(int i=0; i<DISPCNT; i++)
       {
         if ((i%100)==0){System.out.println() ;}if(i>4&&i%5==0){System.out.print(",") ;}
         System.out.print(x[i+2]) ;
    }}}