#include<iostream>
#include<algorithm>
#include<limits.h>
#include<cmath>
#include<string>
#define ll long long
using namespace std;
int main(){
ll n,tests;
cin>>n>>tests;
string s; cin>>s;
while(tests--){
    string t; cin>>t;
    if(t=="pop_back")
        s.pop_back();
    else if(t=="front")
    cout<<s.front()<<'\n';
    else if(t=="back")
    cout<<s.back()<<"\n";
    else if(t=="sort"){
        ll a,b; cin>>a>>b;
        sort(s.begin()+min(a,b)-1,s.begin()+max(a,b));
    }else if(t=="reverse"){
        ll a,b; cin>>a>>b;
        reverse(s.begin()+min(a,b)-1,s.begin()+max(a,b));
    }else if(t=="print"){
        ll num; cin>>num;
        cout<<s[num-1]<<"\n";
    }else if(t=="substr"){
        ll a,b; cin>>a>>b;
        for(int i=min(a,b)-1;i<=max(a,b)-1;i++)
        cout<<s[i];
        cout<<"\n";
    }else if(t=="push_back"){
        char ch; cin>>ch;
        s.push_back(ch);

    }
}
    return 0;
}