Merkkijono

s=input()
p=0
c=""
while c!=s:
    c=s
    for x in range(len(s)):
        if p == s[x]:
            
            beg=s[:x-1]
            end=s[x:]

            while True:
                if len(end)==0:
                    break
                if end[0]==p:
                    end=end[1:]
                else:
                    break
            s=beg+end
            break
            
        p=s[x]
            
print(s)

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: RUNTIME ERROR

Test 4

Verdict: RUNTIME ERROR

Test 5

Verdict: RUNTIME ERROR

Test 6

Verdict: RUNTIME ERROR

Test 7

Verdict: RUNTIME ERROR

Test 8

Verdict: RUNTIME ERROR

Test 9

Verdict: RUNTIME ERROR

Test 10

Verdict: RUNTIME ERROR