Monistus

mj = input('')
vastaus = mj
count = 1

for key, merkki in enumerate(mj):
    if merkki.isdigit():
        vastaus = vastaus.replace(mj[key:key+1+int(merkki)], mj[key+1:key+1+int(merkki)]*2, count)
        count *= 2

print(vastaus)

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: WRONG ANSWER

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: WRONG ANSWER

Test 6

Group: 1, 2

Verdict: WRONG ANSWER

Test 7

Group: 1, 2

Verdict: WRONG ANSWER

Test 8

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 9

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 10

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 11

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 12

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 13

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...

Test 14

Group: 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 7, in <module>
    va...