function mid2_6()
  format long
  n = 64;
  h = 1 / 64;
  x = linspace(0,1,65);
  f = exp(-x);
  w = ones(1, n+1);
  w(2:2:n) = 4;
  w(3:2:n-1) = 2;
  w*f'*h/3
end