题解 | #点击消除#字符串与栈结合

#include <bits/stdc++.h>
using namespace std;

int main() 
{
    string s;
    cin>>s;
    stack<char> a;
    int n=s.size();
    for(int i=0;i<n;i++)
    {
        if((!a.empty())&&a.top()==s[i])
            a.pop();
        else
            a.push(s[i]);
    }
    if(a.empty())
        cout<<0;
    else
    {
        string ss;
        while(!a.empty())
        {
            ss.push_back(a.top());
            a.pop();
        }
        reverse(ss.begin(),ss.end());
        cout<<ss;
    }
    return 0;
}