import sys
input=lambda: sys.stdin.readline().rstrip()
S=input()
while True:
  if S[0]=="ｗ":
    S=S[1:]
  else:
    break
A=[]
B=[]
cur=""
ct=0
for s in S:
  if s=="ｗ" and ct==0:
    A.append(cur)
    cur=""
    ct=1
  elif s=="ｗ":
    ct+=1
  elif ct!=0:
    B.append(ct)
    cur+=s
    ct=0
  else:
    cur+=s
    ct=0
B.append(ct)

n=len(A)
m=max(B)
for i in range(n):
  if B[i]==m:
    print(A[i])