s=list(input())
n=len(s)
l=[]
i=0
while i<n-1:
    if s[i]==s[i+1]:
        l.append(s[i])
        i+=2
    else:
        l.append(s[i])
        i+=1

l.append(s[n-1])
ans=""
for x in l:
    ans+=x
    
print(ans)