Background

Description

Modify and return the given map as follows: for this problem the map may or may not contain the "a" and "b" keys. If both keys are present, append their 2 string values together and store the result under the key "ab".

Format

Input

Output

Samples

"a": "Hi" "b": "There"

{"a": "Hi", "ab": "HiThere", "b": "There"}

"a": "Hi"

{"a": "Hi"}

"b": "There"

{"b": "There"}

Limitation

1s, 1024KiB for each test case.