求L的hack数据，L题采取栈模拟为什么不行呢？

#include<bits/stdc++.h>
#define int long long
using namespace std;
void solve()
{
    int n;
    cin>>n;
    string s;
    cin>>s;
    s=" "+s;
    int i;
    stack<char>q,g;
    map<char,int>p;
    for(i=1;i<=n;i++)
    {
        if(s[i]=='C')
        {
            if(g.size()==0||g.size()==3)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else if(s[i]=='H')
        {
            if(g.size()==1)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else if(s[i]=='I')
        {
            if(g.size()==2)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else if(s[i]=='K')
        {
            if(g.size()==4)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else if(s[i]=='E')
        {
            if(g.size()==5)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else if(s[i]=='N')
        {
            if(g.size()==6)
            g.push(s[i]);
            else
            {
                if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
            }
        }
        else
        {
            if(!q.empty()&&q.top()!=s[i])
                q.pop();
                else
                q.push(s[i]);
        }
    }
    if(g.size()!=7||q.size()>0)
    cout<<"NO";
    else
    cout<<"YES";
}
signed main()
{
    std::ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t;
    cin>>t;
    while(t--)
    {
        solve();
        cout<<endl;
    }
    return 0;
}