763. 划分字母区间 - 力扣（LeetCode）

class Solution:
    def partitionLabels(self, s: str) -> List[int]:
        last_index = {char: idx for idx, char in enumerate(s)}
        partitions = []
        start = end = 0
        
        for i, char in enumerate(s):
            end = max(end, last_index[char])
            if i == end:
                partitions.append(end - start + 1)
                start = i + 1
        
        return partitions