#include <cstdio>
#include <fstream>
#include <set>
#include <vector>

using namespace std;

#define nmax 300005
#define MOD 666013
#define x first
#define y second
#define inf (1000000004)
char s[20];
string temp;
set<int> my_set;
multiset<int> diff;
struct{int max, min;}aint[nmax*3];
vector<pair<int,int> > lista[MOD+4];
int poz_aint = 0;
typedef set<int>::iterator it_set;
multiset<int>::iterator it_diff;

void udpate(int nod, int st, int dr, int poz, int val, int val2){

    if(st == dr){
        aint[nod].max = val;
        aint[nod].min = val2;
        return;
    }
    int mij =(st +dr)/2;
    if (poz <= mij) udpate(nod*2, st, mij, poz, val, val2);
              else udpate(nod*2+1, mij+1, dr, poz, val, val2);

    aint[nod].max = max(aint[nod*2].max, aint[nod*2+1].max);
    aint[nod].min = min(aint[nod*2].min, aint[nod*2+1].min);

}

vector<pair<int,int> >::iterator afla_iterator(int x) {

    int rest = x % MOD;

    for(vector<pair<int,int> >::iterator it=lista[rest].begin(); it!=lista[rest].end(); it++){
        if (it->x == x){
            return it;
        }
    }

    return lista[rest].end();

}

pair<int,int> citeste_buf(){
    int poz = 0;
    pair<int,int> R;
    temp.clear();
    for(; s[poz]>='A'&&s[poz]<='Z'; poz++)temp += s[poz];
    if (temp == "MAX"){
        R.x = 5;
        return R;
    }else if (temp == "MIN"){
        R.x = 4;
        return R;
    }
    for(; s[poz] == ' '; poz++);
    for(; s[poz]>='0' && s[poz]<='9'; poz++){
        R.y = R.y*10 + (s[poz]-'0');
    }
    if (temp == "I"){
        R.x = 1;
        return R;
    }else if (temp == "S"){
        R.x = 2;
        return R;
    }else {
        R.x = 3;
        return R;
    }

}

void rezolva(){

    for(int i=1; i<nmax*3; i++) aint[i].min = inf;

    while(gets(s)!=NULL){
        pair<int,int> aux = citeste_buf();
        if (aux.x == 1){//insert
                int rest = aux.y % MOD;
                if (afla_iterator(aux.y)==lista[rest].end()){
                    ++poz_aint;
                    lista[rest].push_back(make_pair(aux.y, poz_aint));
                    udpate(1,1,nmax, poz_aint, aux.y, aux.y);
                    my_set.insert(aux.y);
                    it_set i = my_set.find(aux.y);
                    it_set last = my_set.end();
                    --last;
                    if (i==my_set.begin()){
                        it_set dr = i;
                        dr++;
                        //printf("pasul : %d ; %d", pas, *dr-*i);
                        if (my_set.size()>=2)diff.insert(*dr-*i);
                    }
                    else if (i==last){//elemntul se afla la capat
                        it_set st;
                        st = i;
                        --st;
                        if (my_set.size()>=2)diff.insert(*i-*st);
                    }else{//e in interior
                        it_set st,dr;
                        st = i; dr = i;
                        --st; dr++;
                        if (my_set.size()>=2)diff.insert(*i-*st);
                        if (my_set.size()>=2)diff.insert(*dr-*i);
                    }

                }
        }
        else if (aux.x == 2){//sterge
                int rest = aux.y % MOD;
                vector<pair<int,int> >::iterator  ii = afla_iterator(aux.y);
                if (ii == lista[rest].end()){
                    printf("-1\n");
                }
                else {
                    int poz = ii->y;
                    udpate(1,1,nmax, poz, -inf, inf);
                    it_set i = my_set.find(aux.y);
                    it_set last = my_set.end();
                    --last;
                    if (i==my_set.begin()){
                        it_set dr = i;
                        dr++;
                        it_diff = diff.find(*dr-*i);
                        diff.erase(it_diff);
                    }
                    else if (i==last){//elemntul se afla la capat
                        it_set st;
                        st = i;
                        --st;
                        it_diff = diff.find(*i-*st);
                        diff.erase(it_diff);
                    }else{//e in interior
                        it_set st,dr;
                        st = i; dr = i;
                        --st; dr++;
                        diff.insert(*dr-*st);
                        it_diff = diff.find(*i-*st);
                        diff.erase(it_diff);
                        it_diff = diff.find(*dr-*i);
                        diff.erase(it_diff);
                    }
                    my_set.erase(i);
                }
        }
        else if (aux.x == 3){//cauta
                int rest = aux.y%MOD;
                if (afla_iterator(aux.y) == lista[rest].end()){//nu l-a gasit
                    printf("0\n");
                }else printf("1\n");//exista
        }
        else if (aux.x == 5){//Max
                //printf("size: %d\n", my_set.size());
                if (my_set.size()<2){
                    printf("-1\n");
                }else printf("%d\n", aint[1].max-aint[1].min);
        }
        else if (aux.x == 4){//Min
                if (my_set.size()<2){
                    printf("-1\n");
                }else printf("%d\n", (*diff.begin()) );
        }

    }

}

int main(){

    freopen("zeap.in", "r", stdin);
    freopen("zeap.out", "w", stdout);

    rezolva();

}