题解 | #查找兄弟单词#

创建一个map用于统计原字符串中每个字母出现的次数，再创建一个map依次统计序列中每个字符串的每个字母出现次数，如果两个字符串长度相等并且每个字母出现的次数相等，且两个字符串不相等，即为兄弟字符串，将其添加到vector中，排序后输出第k个字符串。

#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
using namespace std;

int main() {
    string s;
    int n;
    cin >> n;
    int order;
    vector<string> words;
    vector<string> brothers;
    map<char, int> letters;
    map<char, int> temp;
    for (int i = 0; i < n; i++) {
        cin >> s;
        words.push_back(s);
    }
    cin >> s;
    cin >> order;
    for (char letter : s) {
        if (letters.find(letter) != letters.end()) {
            letters[letter]++;
        } else {
            letters.insert({letter, 1});
        }
    }
    for (string word : words) {
        bool flag = true;
        temp.clear();
        for (char letter : word) {
            if (temp.find(letter) != temp.end()) {
                temp[letter]++;
            } else {
                temp.insert({letter, 1});
            }
        }
        if (temp.size() == letters.size()) {
            for (pair<char, int> element : letters) {
                if (temp.find(element.first) == temp.end()) {
                    flag = false;
                } else {
                    if (temp[element.first] != element.second) {
                        flag = false;
                    }
                }
            }
            if (flag && word != s) {
                brothers.push_back(word);
            }
        }
    }
    sort(brothers.begin(), brothers.end());
    cout << brothers.size() << endl;
    if (order <= brothers.size()) {
        cout << brothers.at(order - 1);
    }
}
// 64 位输出请用 printf("%lld")