Repeating Index in List

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#1

def accum(s):
# your code
list = 

for i in s:
  list.append(i.upper() + i.lower()*s.index(i))
return "-".join(list)

print(accum(“ZpglnRxqenU”)

You can see the return. The problem is that if the leter repeats its first index, how can i fix it ? if first N has index 4 , second N has 9 but it still gets index 4 ?
Thank you

#2

As evidenced, index() always starts from the left edge and stops on the first encounter, hence index 4 on both calls.

Check the documentation to see if we are permitted to specify a starting index.