# -*- coding: utf-8 -*- import codecs import sys sys.stdin = codecs.getreader('utf_8')(sys.stdin) sys.stdout = codecs.getwriter('utf_8')(sys.stdout) A = raw_input() current = 0 mx = 0 for a in A: if a == u"w": current += 1 mx = max(mx, current) else: current = 0 buf = "" old = "" for a in A: if a == u"w": current += 1 if current == mx: print buf exit() else: if old == u"w": buf = "" current = 0 buf += a old = a print ""