2019-11-02 12:07:41 +08:00
|
|
|
|
# 48. 最长不含重复字符的子字符串
|
|
|
|
|
|
|
|
|
|
|
|
## 题目描述
|
|
|
|
|
|
|
|
|
|
|
|
输入一个字符串（只包含 a\~z 的字符），求其最长不含重复字符的子字符串的长度。例如对于 arabcacfr，最长不含重复字符的子字符串为 acfr，长度为 4。
|
|
|
|
|
|
|
|
|
|
|
|
## 解题思路
|
|
|
|
|
|
|
|
|
|
|
|
```java
|
|
|
|
|
|
public int longestSubStringWithoutDuplication(String str) {
|
|
|
|
|
|
int curLen = 0;
|
|
|
|
|
|
int maxLen = 0;
|
|
|
|
|
|
int[] preIndexs = new int[26];
|
|
|
|
|
|
Arrays.fill(preIndexs, -1);
|
|
|
|
|
|
for (int curI = 0; curI < str.length(); curI++) {
|
|
|
|
|
|
int c = str.charAt(curI) - 'a';
|
|
|
|
|
|
int preI = preIndexs[c];
|
|
|
|
|
|
if (preI == -1 || curI - preI > curLen) {
|
|
|
|
|
|
curLen++;
|
|
|
|
|
|
} else {
|
|
|
|
|
|
maxLen = Math.max(maxLen, curLen);
|
|
|
|
|
|
curLen = curI - preI;
|
|
|
|
|
|
}
|
|
|
|
|
|
preIndexs[c] = curI;
|
|
|
|
|
|
}
|
|
|
|
|
|
maxLen = Math.max(maxLen, curLen);
|
|
|
|
|
|
return maxLen;
|
|
|
|
|
|
}
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
2019-11-02 17:33:10 +08:00
|
|
|
|
<div align="center"><img width="320px" src="https://cs-notes-1256109796.cos.ap-guangzhou.myqcloud.com/githubio/公众号二维码-2.png"></img></div>
|
