int d[8d6]{1},s=0,m=8d6;
int@n,@a[n];
sortA(n,a);
rep(i,n){
	s+=a[i];
	rrep(j,a[i],min(m,s+1)){
		if(d[j-a[i]]){
			if(++d[j]>=2){
				m=j;
			}
		}
	}
}
wt(s-2m>0?s-2m:-1);