1064 朋友数 （20 分）

#include <iostream>
#include<set>
using namespace std;
int getFriendNum(int a) {
	int sum = 0;
	while (a) {
		int b = a % 10;
		a = a / 10;
		sum += b;
	}
	return sum;
}
int main()
{
	int n;
	cin >> n;
	set<int> fri;
	for (int i = 0;i < n;i++) {
		int k;
		cin >> k;
		int a=getFriendNum(k);
		fri.insert(a);
	}
	cout << fri.size() << endl;
	set<int>::iterator it;
	for (it = fri.begin();it != fri.end();it++) {
		if (it != fri.begin())cout << " ";
		cout << *it;
	}
	return 0;
}