Problem: For a dictionary $M$ that stores elements formed by a pair of a string key and an integer value, perform a sequence of the following operations. Note that each key in $M$ must be unique.

* insert($key$, $x$): Insert an element formed by a pair of $key$ and $x$ to $M$.
* get($key$): Print the value with the specified $key$. Print 0 if there is no such element.
* delete($key$): Delete the element with the specified $key$.
* dump($L$, $R$): Print all elements formed by a pair of the key and the value such that the key is greater than or equal to $L$ and less than or equal to $R$ in lexicographic order.

Constraints

* $1 \leq q \leq 200,000$
* $1 \leq x \leq 1,000,000,000$
* $1 \leq $ length of $key$ $ \leq 20$
* $key$ consists of lower-case letters
* $L \leq R$ in lexicographic order
* The total number of elements printed by dump operations does not exceed $1,000,000$

Input

The input is given in the following format.


$q$
$query_1$
$query_2$
:
$query_q$


Each query $query_i$ is given by


0 $key$ $x$


or


1 $key$


or


2 $key$


or


3 $L$ $R$


where the first digits 0, 1, 2 and 3 represent insert, get, delete and dump operations.

Output

For each get operation, print the corresponding value.
For each dump operation, print the corresponding elements formed by a pair of the key and the value. For the dump operation, print the elements (a pair of key and value separated by a space character) in ascending order of the keys.

Example

Input

9
0 blue 4
0 red 1
0 white 5
1 red
1 blue
2 red
1 black
1 red
3 w z


Output

1
4
0
0
white 5

Solution (in CPP):

Solution:
#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <map>
#include <numeric>
#include <string>
#include <cmath>
#include <iomanip>
#include <queue>
#include <list>
#include <set>
#include <stack>
#include <cctype>
#include <cmath>

using namespace std;

/* typedef */
typedef long long ll;

/* constant */
const int INF = 1 << 30;
const int NIL = -1;
const int MAX = 10000;
const int mod = 1000000007;
const double pi = 3.141592653589;

/* global variables */

/* function */

/* main */
int main(){

    int q; cin >> q;
    int op, x;
    string l, r;
    string key;
    map<string, int> M;
    using iterator  = decltype(M)::iterator;

    for (int i = 0; i < q; i++) {
        cin >> op >> key;
        switch(op) {
            case 0:
                cin >> x;
                // insert(key, x) :
                // Insert an element formed by a pair of key and x to M
                M[key] = x;
                break;
            case 1:
                // get(key): Print the value with the specified key
                // if M[key] is not exist
                // => M[key] = 0 and return 0
                // exist => return M[key]
                if (M.count(key))
                    cout << M[key] << '\n';
                else
                    cout << 0 << '\n';
                break;
            case 2:
                // delete(key): Delete the element with the specified key
                M.erase(key);
                break;
            case 3:
                cin >> r;
                l = key;
                iterator head = M.lower_bound(l);
                iterator tail = M.upper_bound(r);
                for ( ; head != tail; head++)
                    cout << (*head).first << ' ' << (*head).second << '\n';
                break;
        }
    }

}