format long
a=0;
b=1;
n=64;
h=(b-a)/64;
x=a:h:b;
f=ones(1,65);
for i=1:65
     f(i)=exp(-x(i));
       end
f=f';
w=ones(1,n+1);
w(2:2:n)=4;
w(3:2:n-1)=2;

s=w*f*h/3