## JDCC '17 Contest 3 S1 - <<<<3<33<333

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Points: 3 (partial)
Time limit: 2.0s
Memory limit: 64M

Problem type

Vedant really wants the recruiters at a certain internet search company to know how much he wants to work there, so he adds a bunch of cute hearts at the end of his resume.

A cute heart is defined as one of the following:

• <3 is a cute heart
• <x3, where x is a cute heart
• xy, where x and y are cute hearts

For example, <<<333, <<3<33, <3<3 and <<<<3<33<333 are all cute hearts, but <<3, <33< and 3<3< are not cute hearts.

Help Vedant figure out whether the text he added to his resume is a cute heart!

#### Input

The input is a single string with no more than $$10^5$$ characters, with each character being either < or 3.

#### Output

Output <3 if the text is a cute heart, and </3 otherwise.

#### Sample Input 1

<<<33<33

#### Sample Output 1

<3

#### Explanation for Sample Input 1

All the hearts are nested correctly within each other.

#### Sample Input 2

<3<<<3333

#### Sample Output 2

</3

#### Explanation for Sample Input 2

The last character, 3, is not matched with a <, so it can’t be a cute heart.