题解 | #提取不重复的整数#

#include <iostream>
#include <deque>
#include <unordered_set>
using namespace std;
int main(){ 
    int num;
    deque<int> ans;
    unordered_set<int> help;
    cin >> num;
    while(num != 0){
        if(help.count(num % 10) == 0){
            ans.push_back(num % 10);
            help.insert(num % 10);
            num /= 10;
        }else{
            num /= 10;
        }
    }
    while(!ans.empty()){
        cout << ans.front();
        ans.pop_front();
    }
    return 0;
}

利用哈希表去重，利用数组顺序输出