S = input()

n = len(S)
ANS = []
i = 0
while i < n:
    if i == n - 1:
        ANS.append(S[i])
        i += 1
    elif S[i] == S[i + 1]:
        ANS.append(S[i])
        i += 2
    else:
        ANS.append(S[i])
        i += 1
print(''.join(ANS))