S = input()
i = 0
l = []
while i < len(S):
    if i == len(S)-1:
        l.append(S[i])
        i += 1
        continue
    l.append(S[i])
    if S[i+1] == S[i]:
        i += 2
    else:
        i += 1
print("".join(l))