s = input()
n = len(s)
if n == 1:
    print(s)
    exit()
i = 0
ans = ""
while i < n - 1:
    if s[i] == s[i + 1]:
        ans += s[i]
        i += 2
    else:
        ans += s[i]
        i += 1
if s[-2] != s[-1]:
    ans += s[-1]
print(ans)