Take-Away Game

Difficulty: 1300 2000 ms 128 MB

math games

A pile holds N stones. Players alternate removing between 1 and K stones; whoever takes the last stone wins. Both play perfectly — who wins?

Input: one line with two integers N and K.

Output: FIRST or SECOND.

Constraints:

• 1 ≤ N ≤ 10¹⁸
• 1 ≤ K ≤ 10⁹

Sample Tests

10 3

FIRST

8 3

SECOND

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