Look and Say

Difficulty: 1200 2000 ms 128 MB

implementation strings

The look-and-say sequence starts 1, 11, 21, 1211, 111221, ...: each term describes the previous term's digit runs aloud. Print term N.

Input: one integer N.

Output: the N-th term.

Constraints:

• 1 ≤ N ≤ 25

Sample Tests

4

1211

1

1

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