edit on this code and solve the question

function [x, flag] = newtonsolver_template(x0, tol)

flag = 1;
r0 = zeros();
J = zeros();
x = zeros();
rtest = zeros();

r0(1) = ;
r0(2) = ;

r = r0;
counter = 1;
while (norm(r)/norm(r0) > tol)

J(1,1) = ;
J(1,2) = ;
J(2,1) = ;
J(2,2) = ;

s = Jr;
lambda = 1.0;
while (1)
x = x0 – lambda*s;
rtest(1) = ;
rtest(2) = ;
if (norm(rtest) < 1.001*norm(r))
r = rtest;
x0 = x;
break;
else
lambda = lambda/2;
end
end

counter = counter + 1;
disp(norm(r))
if counter == 100
flag = 0;
break;
end

end

end