Problem 74. Balanced number

there is a problem with the test.
it does not accept the following code:
s1=[]
s2=[]
l=length(s)
if mod(l,2)~= 0
for i = 1:ceil(length(s)/2)-1
s1 = [s1,str2double(s(i))]
end
for i = ceil(length(s)/2)+1:l
s2=[s2,str2double(s(i))]
end
else
for i = 1:ceil(length(s)/2)
s1 = [s1,str2double(s(i))]
end
for i = ceil(length(s)/2)+1:l
s2=[s2,str2double(s(i))]
end
end

if sum(s1)==sum(s2)
tf = 1
else
tf = 0
end