//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<n; ++i)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;
using ll = int64_t;
using ld = long double;
using P = pair<int, int>;
using vs = vector<string>;
using vi = vector<int>;
using vvi = vector<vi>;
template<class T> using PQ = priority_queue<T>;
template<class T> using PQG = priority_queue<T, vector<T>, greater<T> >;
const int INF = 100010001;
const ll LINF = (ll)INF*INF*10;
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);}
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);}
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) { return is >> p.first >> p.second;}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) { return os << p.first << ' ' << p.second;}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int q;
    cin >> q;
    map<string, int> mp;
    while(q--) {
        int t;
        cin >> t;
        if(t == 0) {
            string key;
            int x;
            cin >> key >> x;
            mp[key] = x;
        } else if(t == 1) {
            string key;
            cin >> key;
            cout << (mp.count(key)?mp[key]:0) << '\n';
        } else if(t == 2) {
            string key;
            cin >> key;
            mp.erase(key);
        } else {
            string l, r;
            cin >> l >> r;
            for(auto itr = mp.lower_bound(l); itr != mp.upper_bound(r); itr = next(itr, 1)) {
                cout << *itr << '\n';
            }
        }
    }
}
