Invert a Dictionary

Lab Python Intermediate 20 points

Read n lines of key value. Build a dict, then invert it (values become keys). Print the inverted pairs sorted by the new key as key -> value.

Input

Line 1: n. Then n lines (values are unique).

Output

n lines.

Example

Input

3
red 1
green 2
blue 3

Output

1 -> red
2 -> green
3 -> blue

Sample input available Sample output available

Editor

Python

Hints

dict() accepts a sequence of 2-item pairs.

A dict comprehension: {v: k for k, v in d.items()}.

Solution explanation

Dict comprehensions build dictionaries the same way list comprehensions build lists.

Show solution

n = int(input())
d = dict(input().split() for _ in range(n))
inverted = {v: k for k, v in d.items()}
for k in sorted(inverted):
    print(f"{k} -> {inverted[k]}")

Output

Answer