q1:=sqr(2);
input m;
input x1;
input y1;
m1:=n/m;
x2:=x1;
y2:=y1;
for i:=1 to m1;
for j:=1 to m;
x:=x2;
y:=y2;
p:=h*val(f$);
y:=y+0.5*p;
q:=p;
x:=x2+0.5*h;
p:=h*val(f$);
y:=y+(1-q1*0.5)*(p-q);
q:=(3/q1-2)*q+(2-q1)*p;
p:=h*val(f$);
y:=y+(1+1/q1)*(p-q);
q:=(2+q1)*p-(2+3/q1)*q;
x:=x2+h;
p:=h*val(f$);
y2:=y+p/6-q/3;
x2:=x2+h;
next j;
next i;
end;