题解 | #删除字符串中出现次数最少的字符#

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

int main() {
    string str;
    unordered_map<char, int> Map;
    int Min = 20;
    cin >> str;
    for(int i = 0; i < str.length(); i++){
        Map[str[i]] ++;
    }
    vector<char> delChar;
    for(auto it : Map){
        if(it.second < Min){
            Min = it.second;
        }
    }
    for(auto it : Map){
        if(it.second == Min) delChar.push_back(it.first);
    }
    for(int i = 0; i < str.length(); i++){
        auto it = find(delChar.begin(), delChar.end(), str[i]);
        if(it != delChar.end()){
           str.replace(i, 1, ""); 
           i--;//删除一个字符后后面的字符会往前移
        }
    }
    cout << str << endl;
    return 0;
}