function z= euler_putc(a,b,y0,h,maxits)
t(1)=a;
w(1)=y0;
i=a;
while i<=b && i<=maxits
    w(i)=w(i-1) + h * fun(t,w(i-1));
    t(i)=a + i * h;
end 
z = [t;w]