int main()
{
while(~scanf(“%d”,&n))
{
sum = 0,ans = 0;
for(int i=0;i<n;i++)
{
scanf(“%d”,&a[i]);
sum += a[i];
}
if(n<=3)
ans = 1024;
else
if(n==4)
for(int i=0;i<4;i++)
if(mult(sum-a[i]))
ans = 1024;
if(ans!=1024)
solve();
printf(“%d\n”,ans);
}
return 0;
}