Merkkijono

k = input()
k = list(k)
x = True
while x == True:
    x = False
    for i in k[:-1]:
        r = False
        try:
            for j in k[k.index(i)+1]:
                if i == j:
                    k.remove(j)
                    r = True
            if r == True:
                k.remove(i)
                x = True
        except:
            break
print ("".join(k))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER