def fnf(x):=3*-sin((x+y)/2);
fef fng(x):=3*y-cos((x-y)/2);
def fnh(x):=3-0.5*cos((x+y)/2);
fni(x):=-0.5*cos((x+y)/2);
fnj(x):=0.5*sin((x-y)/3);
fnk(x):=3-0.5*sin((x-y)/2);
input l,e;
input x,y;
for p:=1 to l;
f:=fnf(x);
g:=fng(x);
h:=fnh(x);
i:=fni(x);
j:=fnj(x);
k:=fnk(x);
if h*k-j*i=0 then l1;
x1:=(-f*k+g+i)/(h*k-j*i);
y1:=(-g*h+f*j)/(h*k-j*i);
x2:=x+x1;
y2:=y+y1;
if abs(x-x2)
y:=y2;
next p;
p:=p-1;
label l2;
print x2,x-x2,y2,y-y2;
print p;
label l1;
print "no converge";
end;