1064 朋友数 (20分)

#include <iostream>
#include <set>
using namespace std;
int main(){
    int n;
    cin >> n;
    string s;
    set<int> st;//set容易可以自动排序，而且去重
    for (int i=0;i<n;i++){
        cin >> s;
        int sum = 0;
        for (int j=0;j<s.length();j++){
            sum += s[j]-'0';
        }
        st.insert(sum);
    }
    cout << st.size() << endl;
    int flag = 0;//flag用来输出空格，真是长了个猪脑
    for (set<int>::iterator it = st.begin();it != st.end();it++){ //迭代器访问
        if (flag==1) cout << " ";
        cout << *it;
        flag=1;
    }
    return 0;
}


#include <iostream>
using namespace std;
int a[40]={0};
int main(){
    int n,sum=0;
    cin >> n;
    for (int i=0;i<n;i++){
        int sum = 0;
        string s;
        cin >> s;
        for (int j=0;j<s.length();j++){
            sum += s[j]-'0';
        }
        a[sum]=1;
    }
    int cnt = 0;
    for (int i=0;i<40;i++){
        if (a[i]==1) cnt++;
    }
    cout << cnt << endl;
    int flag = 0;
    for (int i=0;i<40;i++){
        if (a[i]==1){
            if (flag==1) cout << " ";
            cout << i;
            flag=1;
        }
    }
    return 0;   
}