import re

S = input()

w = 'ｗ'
while S and S[0] == w:
    S = S[1:]

reg = re.compile('^[^ｗ]+ｗ+')
s = S
cands = []
while m := reg.match(s):
    t = m.group(0)
    if t[0] != w:
        cands.append(t)
    s = s[len(t):]


def count_w(s: str) -> int:
    for i in reversed(range(len(s))):
        if s[i] != w:
            return len(s) - i

    assert False


xs = [(s, count_w(s)) for s in cands]
if not xs:
    print()
    exit()

_, max_wcnt = max(xs, key=lambda x: x[1])
for s, wcnt in xs:
    if wcnt == max_wcnt:
        print(s[:wcnt])