#include <bits/stdc++.h>
using namespace std;
int cnt[200000],a[200000];
int main(){
	int n,x,ans=0;
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>x;
		int sum=0;
		while(x){
			sum+=x%10;
			x/=10;
		}
		cnt[sum]++;
	}
	for(int i=0;i<=200000;i++){
		if(cnt[i]>0){
			ans++;
			a[ans] = i;
		}
		
	}
	cout<<ans<<"\n";
	for(int i=1;i<=ans;i++){
		if(i!=ans)cout<<a[i]<<" ";
		else cout<<a[i]<<"\n";
	}
	return 0;
}