# Partition Labels

A string`S`of lowercase letters is given. We want to partition this string into as many parts as possible so that each letter appears in at most one part, and return a list of integers representing the size of these parts.

**Example 1:**

```
Input:
 S = "ababcbacadefegdehijhklij"

Output:
 [9,7,8]

Explanation:

The partition is "ababcbaca", "defegde", "hijhklij".
This is a partition so that each letter appears in at most one part.
A partition like "ababcbacadefegde", "hijhklij" is incorrect, because it splits S into less parts.
```

**Note:**

```
S will have length in range [1, 500].
S will consist of lowercase letters ('a' to 'z') only.
```

分析

自己做法：双指针，counter Str和辅助set。 counter == len(set)就可以断开一段，s=e重新开始

```
class Solution:
    def partitionLabels(self, S: str) -> List[int]:

        mm = collections.Counter(list(S))
        cnt=s=e=0
        l = len(S)
        ss = set()
        res = []

        while e < l:
            if mm[S[e]] == 1:
                cnt += 1
            ss.add(S[e])
            mm[S[e]] -= 1
            e += 1
            if cnt == len(ss):
                res.append(e-s)
                s = e
                ss = set()
                cnt = 0
        return res
```

类似贪心法

这个区间内所有数最大的范围作为last。i到了那个last就是一段。

```
class Solution:
    def partitionLabels(self, S: str) -> List[int]:
        mm = {}
        for i,v in enumerate(S):
            mm[v] = i

        ll = len(S)
        s = last = 0
        res = []

        for i in range(ll):
            last = max(last, mm[S[i]])#类似贪心算法，这个区间内所有数最大的范围作为last。到了那个last就是一段
            if i == last:
                res.append(last - s + 1)
                s = last + 1
        return res
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://nataliekung.gitbook.io/ladder_code/qiang-hua-4-shuang-zhi-zhen-ff09/partition-labels.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.