s = "ababcbacadefegdehijhklij"

Output: [9, 7, 8]

Character	Last index
a	        8
b	        5
c	        7
d	        14
e	        15
f	        11
g	        13
h	        19
i	        22
j	        23
k	        20
l	        21

i	s[i]	last[s[i]]	end=max(end,last[s[i]])	Partition
0	a	        8	    8
1	b	        5	    8
2	a	        8	    8
...	...	        ...	    ...
8	a	        8	    8   ✅	Partition [0–8] → size 9
9	d	        14	    14
10	e	        15	    15
...	...	        ...	    ...
15	e	        15	    15 ✅	Partition [9–15] → size 7
16	h	        19	    19
...	...	        ...	    ...
23	j	        23	    23 ✅	Partition [16–23] → size 8

class Solution:
    def partitionLabels(self, s: str) -> List[int]:
        res = []
        i = 0
        while i < len(s):
            end = s.rfind(s[i])  # last index of current char
            j = i
            while j < end:
                end = max(end, s.rfind(s[j]))
                j += 1
            res.append(end - i + 1)
            i = end + 1
        return res

class Solution:
    def partitionLabels(self, s: str) -> List[int]:
        last = {c: i for i, c in enumerate(s)}
        res = []
        start = end = 0

        for i, c in enumerate(s):
            end = max(end, last[c])
            if i == end:  # one partition closed
                res.append(end - start + 1)
                start = i + 1
        return res