Race to N

Difficulty: 1200 2000 ms 128 MB

math games

Players alternately add 1, 2 or 3 to a running total starting at 0; whoever says exactly N wins. Who wins with perfect play?

Input: one integer N.

Output: FIRST or SECOND.

Constraints:

• 1 ≤ N ≤ 10¹⁸

Sample Tests

4

SECOND

7

FIRST

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