# http://c...content-available-to-author-only...e.com/questions/54105/all-your-bijective-base-are-belong-to-us
#M="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz<=>"
#M="0123456789"+"".join(map(chr,range(65,91)+range(97,123)))+"<=>"
#u="".join(map(chr,range(65,91)));M="0123456789"+u+u.lower()+"<=>"
#M="".join(map(chr,range(48,58)+range(65,91)+range(97,123)))+"<=>"
R=range;M="".join(map(chr,R(48,58)+R(65,91)+R(97,123)))+"<=>"
b,s,o=input()
F=M.find
e=F(o)<2
B=lambda n:n and B(n/F(o)-e)+M[n%F(o)+e]or""
n=B(sum(F(s[~j])*F(b)**j for j in R(len(s))))
i=n.find('0')
n=list(n)
while-~i:n=n[:i-1]+[M[F(n[i-1])-1]]+[o]+n[i+1:];n=n["0"==n[0]:];i="".join(n).find('0')
print"".join(n)
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