OnlineJudge 3 现已推出。点此体验新版：e--Number game | SDUT OnlineJudge
Time Limit: 2000 ms Memory Limit: 65536 KiB
Dreamtale loves playing with numbers. He only knows prime numbers that are digits yet. These numbers are 2, 3, 5 and 7, he came up a game that were connected with them.
Deamtale wants to find the minimum number of length n, such that it is simultaneously divisible by all numbers Dreamtale already knows (2, 3, 5 and 7). Help him with that.
A number's length is the number of digits in its decimal representation without leading zeros.
A single input line contains a single integer n (1≤n≤10^5).
Print a single integer — the answer to the problem without leading zeroes, or "-1" (without the quotes), if the number that meet the problem condition does not exist.