program px1(input,output);
var
an : array [1..100000] of integer;
n, i,j,k,maxj,sum,s,temp1,temp2 : integer;
begin
readln(n);
for i:=1 to n do read(an[i]); readln;
maxj:=0;
for i:=1 to n-2 do
begin
temp1:=an[i];temp2:=i+1;
for j:=i+2 to n do
begin
sum:=temp1+an[j]; s:=0; k:=temp2;
while (k<j) and (s<=sum) do
begin
s:=s+an[k];k:=k+1
end;
if s=sum then maxj:=j
end
end;
writeln(maxj)
end.
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