ll n,s[2d5],*p=s+1,i,j,k,r=1d18;
{
	rd(n,p(n));
	sort(p,p+n);
	s[1..n]+=s[0..];
	r<?=s[i=(0..n)]*2-s[j=i/2]-s[i-j]-s[k=i+n>>1]-s[i+n-k]+s[n];
	wt(s[n]==s[1]*n|r);
}