function piguji=buffon(llength,mm)
%llength 是針的長度
%mm 是隨機實驗次數
frq=0;
xrandnum = unifrnd(0,0.5,1,mm);
phi= unifrnd(0,pi,1,mm);
for ii=1:mm
    if (xrandnum(1,ii)<=(llength*sin(phi(1,ii))/2))
        frq=frq+1;
    end    
end    
piguji=2*llength/(frq/mm)