大大大大大大大模拟

#include<bits/stdc++.h>
using namespace std;
queue<char> A;//存两个人的牌
queue<char> B;
vector<char> v;//存桌上的牌
string a, b;
map<char, int> r;//记录某张牌在哪个位置
int t;
int main() {
    cin >> a >> b;
    for (int i = 0; i < a.size(); i++)
        A.push(a[i]);
    for (int i = 0; i < b.size(); i++)
        B.push(b[i]);
    int cnt = 0;
    bool first = true;
    while (!A.empty() and !B.empty()) {
        if (t >= 100000) {
            cout << -1 << endl;
            return 0; 
        }
        t++;
        if (first) {
            char now = A.front();
            v.push_back(A.front());
            if (r.count(A.front())) {
                int index = r[A.front()];
                for (int i = cnt; i >= index; i--) {
                    A.push(v[i]);
                    r.erase(v[i]);
                    v.pop_back();
                    cnt--;
                }
                cnt++;
                A.pop();
                continue;
            }
            r[A.front()] = cnt++;
            A.pop();
        }
        if (A.empty() or B.empty())break;
        char now = A.front();
        v.push_back(B.front());
        if (r.count(B.front())) {
            int index = r[B.front()];
            for (int i = cnt; i >= index; i--) {
                B.push(v[i]);
                r.erase(v[i]);
                v.pop_back();
                cnt--;
            }
            B.pop();
            cnt++;
            first = false;
            continue;
        }
        first = true;
        r[B.front()] = cnt++;
        B.pop();
    }
    if (A.empty()) {
        int k = B.size();
        for (int i = 0; i < k; i++)
            cout << B.front(), B.pop();
    }
    else {
        int k = A.size();
        for (int i = 0; i < k; i++)
            cout << A.front(), A.pop();
    }
    return 0;
}