function [X, f1]=DeJong5(Xi)
f1=0;
f2=0;
n=2;
j=1:25;
a=[-32 -16 0 16 32 -32 -16 0 16 32 -32 -16 0 16 32 -32 -16 0 16 32 -32 -16 0 16 32;-32 -32 -32 -32 -32 -16 -16 -16 -16 -16 0 0 0 0 0 16 16 16 16 16 32 32 32 32 32];
                         %setting boundary and function
LL = -65.536;              %Lower limit
UL = 65.536;               %Upper limit
X = LL+rand(1,n)*(UL-LL);  % step1 Choose starting design X, 
for j=1:1:25
    for n=1:1:2
        f2=f2+(X(n)-a).^6;
    f1=f1+0.002+1/j+f2;
end
end