Geometric or Not

Difficulty: 1300 2000 ms 128 MB

math

Is the integer sequence a geometric progression (each term the previous times a fixed ratio)? The ratio need not be an integer conceptually, but all TERMS are integers.

Input: the first line has N; the second line has N integers.

Output: YES or NO (length ≤ 2 is YES).

Constraints:

• 1 ≤ N ≤ 60
• |terms| ≤ 10¹⁸

Sample Tests

4
2 6 18 54

YES

3
1 2 3

NO

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