中国DOS联盟

@echo off&title 计算圆周率 by plp626@cn-dos.net
setlocal enabledelayedexpansion
if not %1.==. (set c=%1) else set c=100
set/a c=(c*100/3)+70,cc=c/10,count=0
for /l %%a in (1 1 %cc%)do set/a f_%%a=2000
for /l %%a in (%c% -132 100)do (set/a n=%%a/10,m=2*n-1
set/a "d=f_!n!*10000,f_!b!=d%%m,d=d/m,n-=1"
for /l %%b in (!n! -1 1)do (set/a n=%%b,m=2*n-1
   set/a "d=d*n+f_!n!*10000,f_!n!=d%%m,d=d/m,n-=1"
)
set/a "an=e+d/10000,e=d%%10000"
if !an! lss 1000 set an=000!an!
set/p=!an:~-4!<nul
)
echo\&echo/&set/p=数学爱好者加我QQ:************，

k = 1: s = 1: t = 1: m = 1
time_ = timer
While Abs(t) > 0.0000001
k = k + 2  
m = -m  
t = m / k  
s = s + t  
Wend
tt = timer - time_
MsgBox tt & vbCrLf & "圆周率π=" & 4 * s

#include < stdio.h>
long a=10000, b, c=2800, d, e, f[2801], g; 
main(){
for(;b-c;)f[b++]=a/5; 
for(;d=0,g=c*2;c-=14,printf("%.4d",e+d/a),e=d%a) 
for(b=c;d+=f[b]*a,f[b]=d%--g,d/=g--,--b;d*=b);
} 

#include < stdio.h>
long b, c=2800, d, e, f[2801]; 
main(){
    while(b-c!=0){
        f[b]=2000;
        b++;
        }

    while(c!=0){
        b=c;
        d=f[b]*10000;
        f[b]=d%(b*2-1);
        d=d/(b*2-1);
        --b;
        while(b!=0){
            d=d*b+f[b]*10000;
            f[b]=d%(b*2-1);
            d=d/(b*2-1);
            --b;
            }
        c-=14;
        printf("%.4d",e+d/10000);
        e=d%10000;
        }
    }