#PyPy用
from sys import stdout
wt=stdout.write
def main():
  S=input()
  if len(S)<2:
    print(S)
    return
  wt(S[0])
  a=S[0]
  for i in range(1,len(S)):
    if S[i]!=a:
      wt(S[i])
    a=S[i]
  wt("\n")
  return

main()