题解 | #查找兄弟单词#

#include <iostream>
#include <string>
#include <vector>
#include <set>
#include <unordered_map>
using namespace std;

bool isBrother(string& word, string& target){
    if(word.size() != target.size()){
        return false;
    }
    if(word == target){
        return false;
    }
    unordered_map<char, int> dic;
    for(int i = 0; i < target.size(); ++i){
        ++dic[target[i]];
    }
    for(int i = 0; i < word.size(); ++i){
        if(dic.count(word[i])){
            --dic[word[i]];
            if(dic[word[i]] == 0){
                dic.erase(word[i]);
            }
        }
        else{
            return false;
        }
    }
    return dic.empty() ? true : false;
}

int main(int argc, char* argv[]){
    int n;
    cin >> n;
    multiset<string> dic;
    for(int i = 0; i < n; ++i){
        string word;
        cin >> word;
        dic.insert(word);
    }
    string target;
    cin >> target;
    int k;
    cin >> k;

    int count = 0;
    string kBrother;
    for(auto word : dic){
        if(isBrother(word, target)){
            ++count;
            if(count == k){
                kBrother = word;
            }
        }
    }
    cout << count << endl;
    if(!kBrother.empty()){
        cout << kBrother << endl;
    }

    return 0;
}