CF_B. Зеркало в строке_послать_когда_откроется_дорешка

#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <stack>
#include <set>
#include <map>
#define pii pair <int,int>
using namespace std;
using ll = long long;
using ld = long double;
void cv(vector <int> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvs(vector <string> v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

bool les(string a, string b){
    //cout<<"a b = "<<a<<" "<<b<<"\n";
    bool r = 0;
    if (a < b || a == b && a.size() < b.size()){
        return 1;
    }
    else if (a == b) return 0;
    else {
        int ai=a.size()-1, bi=b.size()-1;
        while (ai >= 0 && bi >= 0){//cout<<"GO\n";
            a += a[ai];
            b += b[bi];
            //cout<<"ai bi = "<<ai<<' '<<bi<<"\n";
            //cout<<"a b = "<<a<<' '<<b<<"\n";
            if (a < b){//cout<<"a < b\n";
                r = 1;
                break;
            }
            else if (b > a){//cout<<"b >= a\n";
                r = 0;
                break;
            }
            else{//cout<<"NEXT\n";
               ai--;
               bi--;
               //cout<<"ai bi = "<<ai<<' '<<bi<<"\n";
               if (ai < 0 || bi < 0) break;
            }

        }
    }
    //cout<<"DONE\n";
    return r;
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t=1,n=1e5;
    //cin>>t;
    char l='x';
    for (int i=0;i<t;++i){
        //cin>>n;
        string s="";
        string mn = "";
        for (int j = 0;j<(n+1)/2;++j){
            mn += 'z';
        }
        for (int j=0;j<n;++j){
            //cin>>l;
            //cout<<"J = "<<j<<"\n";
            s += l;
            if ( les(s, mn) ){
                mn = s;
                //cout<<"mn = "<<mn<<"\n";
            }
        }

        for (int i = mn.size()-1; i >= 0;--i){
                //cout<<"i = "<<i<<"\n";
            mn += mn[i];
        }
        cout<<mn<<"\n";
    }
}
/*
10
zdbaaaaabbbde
zdbaabdz
*/