Problem:
Map: Delete

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 $key$.

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 $key$

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

Output

For each get operation, print an integer in a line.

Constraints

$1 \leq q \leq 200,000$

$1 \leq x \leq 1,000,000,000$

$1 \leq $ length of $key$ $ \leq 20$

$key$ consits of lower case letters

Sample Input 1

8
0 blue 4
0 red 1
0 white 5
1 red
1 blue
2 red
1 black
1 red

Sample Output 1

1
4
0
0

Solution in Python3 (judge verdict: Accepted)

import sys
n = int(input())
d = {}
lines = sys.stdin.readlines()
ans = [None] * n
for i in range(n):
    q, *arg = lines[i].split()
    if q == '0':    # insert
        d[arg[0]] = arg[1]
    elif q == '1':  # get
        ans[i] = d[arg[0]] if arg[0] in d else 0
    elif q == '2':  # delete
        if arg[0] in d:
            del d[arg[0]]

[print(x) for x in ans if x is not None]