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# 763.Partition-Labels

## 题目描述

A string S of lowercase English 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:
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 English letters ('a' to 'z') only.

## 代码

### Approach #1 Greedy

Time: O(N) && Space: O(1)
class Solution {
public List<Integer> partitionLabels(String S) {
int[] last = new int[26];
for (int i = 0; i < S.length(); i++) {
last[S.charAt(i) - 'a'] = i;
}
int j = 0, anchor = 0;
List<Integer> ans = new ArrayList();
for (int i = 0; i < S.length(); i++) {
j = Math.max(j, last[S.charAt(i) - 'a']);
if (i == j) {