b="([{<"
d=")]}>"
f(e:c)n(x:r)|x!b=y b!!n:f(y d!!n:e:c)(n+1)r|x!d=e:f c(n-1)r|1<3=x:f(e:c)n r
f c n s=s
bWFpbiA9IGludGVyYWN0ICQgZiIgIjAKCmI9IihbezwiCmQ9IildfT4iCnk9Y3ljbGUKKCEpPWVsZW0KZihlOmMpbih4OnIpfHghYj15IGIhIW46Zih5IGQhIW46ZTpjKShuKzEpcnx4IWQ9ZTpmIGMobi0xKXJ8MTwzPXg6ZihlOmMpbiByCmYgYyBuIHM9cw==