#include <bits/stdc++.h> using namespace std; int a[50010]; int main() { int n; cin>>n; for(int i=1;i<=n;++i) cin>>a[i]; sort(a+1,a+n+1); int m=unique(a+1,a+n+1)-a-1; int id=1; for(int i=1;i<=n;++i) if(i==1||a[i]!=a[i-1]) { a[id]=a[i]; ++id; } for(int i=1;i<id;++i) cout<<a[i]<<" "; cout<<endl; cout<<id-1; return 0; }