import sys
i=sys.stdin.readlines()
print[''.join(c for c in l if c in i[0])for l in i[1:]if set(i[0])<set(l)][0]

aW1wb3J0IHN5cwppPXN5cy5zdGRpbi5yZWFkbGluZXMoKQpwcmludFsnJy5qb2luKGMgZm9yIGMgaW4gbCBpZiBjIGluIGlbMF0pZm9yIGwgaW4gaVsxOl1pZiBzZXQoaVswXSk8c2V0KGwpXVswXQ==

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