#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>

int main(){
    int n;
    while(cin >> n,n){
        
        // ?????????????????????????????±
        priority_queue<pii,vector<pii>,greater<pii>> pq;
        
        // ?????\??????????????????????´???????????????????
        map<int,vector<pii>> mp;
        
        // ??????????????????????????????->?????\??????
        map<int,int> endtoi;
        
        pq.push(make_pair(0, 1000000000));
        
        for(int i=0;i<n;i++){
            char c;cin >> c;
            if(c == 'W'){
                int i,s;
                cin >> i >> s;
                while(s > 0){
                    pii x = pq.top();
                    pq.pop();
                    if(s <= x.second - x.first){
                        pq.push(make_pair(x.first + s, x.second));
                        mp[i].push_back(make_pair(x.first, x.first + s - 1));
                        endtoi[x.first + s - 1] = i;
                        s = 0;
                    } else {
                        s -= x.second - x.first;
                        mp[i].push_back(make_pair(x.first, x.second - 1));
                        endtoi[x.second - 1] = i;
                    }
                }
            }
            if(c == 'D'){
                int i;
                cin >> i;
                for(int unsigned j = 0; j < mp[i].size(); j++){
                    pq.push(make_pair(mp[i][j].first,mp[i][j].second+1));
                    endtoi.erase(mp[i][j].second);
                }
                mp.erase(i);
            }
            // ?????°???
            if(c == 'R'){
                int p;
                cin >> p;
                auto it = endtoi.lower_bound(p);
                if(it == endtoi.end()){
                    cout << -1 << endl;
                    continue;
                }
                int i = it->second;
                
                bool isInRange = false;
                for(int unsigned j = 0;j<mp[i].size();j++){
                	if(mp[i][j].first <= p && p <= mp[i][j].second){
                		isInRange = true;
                	}
                }
                if(isInRange){
                    cout << i << endl;
                } else {
                    cout << -1 << endl;
                }
            }
        }
        cout << endl;
    }
	return 0;
}