3885: ucyhf
[Creator : ]
Description
time limit per test
2 secondsmemory limit per test
64 megabytesinput
standard inputoutput
standard outputqd ucyhf yi q fhycu dkcruh mxeiu huluhiu yi q tyvvuhudj fhycu dkcruh. oekh jqia yi je vydt jxu djx ucyhf.
Input
jxu ydfkj sediyiji ev q iydwbu ydjuwuh d (1≤d≤11184) − jxu edu-rqiut ydtun ev jxu ucyhf je vydt.
Output
ekjfkj q iydwbu dkcruh.
Examples
Input
1
Output
13