Cf_contest_4_L

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

    int main()
    {

        int n, x;
        cin >> n >> x;

         string s;
         cin >> s;
        while(x--)
        {
             string t;
             cin >>  t;
             if(t == "substr")
             {
                int a ,b;
                cin >> a >> b;
                a--;
                string p = s.substr(a,b-a+1);
                cout << p << endl;
             }
             else if( t == "sort")
             {
                int a , b ;
                cin >> a >> b;
                a--;
                if(a > b)
                    swap(a,b);
                sort(s.begin()+a , s.begin()+b);
             }
             else if(t == "pop_back")
             {
                s.pop_back();
             }
             else if(t == "front")
             {
                char c = s.front();
                cout << c << endl;
             }
             else if(t == "back")
             {
                char ch = s.back();
                cout << ch << endl;
             }
             else if(t == "reverse")
             {
                int a,b;
                cin >> a >> b;
                a--;
                if(a > b)
                    swap(a,b);
                reverse(s.begin()+a,s.begin()+b);
             }
             else if(t == "push_back")
             {
                char c;
                cin >> c;
                s.push_back(c);
             }
             else if(t == "print")
             {
                int p ;
                cin >> p;
                cout << s[p-1];
             }

        }
            return 0;

    }