Monistus

l = input()
i = -1
while True:
  i+=1
  s = l[i]
  if s.isdigit():
    g = str((l[(i+1):i+int(s)+1]))
    h = 0
    j = 0
    while j < len(g) and h==0:
      if g[j].isdigit():
        i = l.index(g[j])-2
        l=l.replace(str(s),g,1)  
        h = 1
      j+=1
    if h == 0:
      l=l.replace(str(s),g,1)
      i+=len(g)

  elif i == len(l)-1:
    break
print(l)

Test 1

Group: 1, 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 5, in <module>
    s = l[i...

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 5, in <module>
    s = l[i...

Test 5

Group: 1, 2

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 5, in <module>
    s = l[i...

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 2

Verdict: TIME LIMIT EXCEEDED