n=1
require'date'
f=->{d=Date.today
(s=d.strftime('%Y%m%d').to_i
return s if s%n<1
d-=1)while d.year>0
-1}
n=4
puts f[]
n=7
puts f[]
n=90000
puts f[]
bj0xIAoKcmVxdWlyZSdkYXRlJwpmPS0+e2Q9RGF0ZS50b2RheSAKKHM9ZC5zdHJmdGltZSgnJVklbSVkJykudG9faQpyZXR1cm4gcyBpZiBzJW48MQpkLT0xKXdoaWxlIGQueWVhcj4wCi0xfQoKCm49NApwdXRzIGZbXQoKbj03CnB1dHMgZltdCgpuPTkwMDAwCnB1dHMgZltdCgo=