LeetCode 算法入门 Day6 滑动窗口 Java

3. 无重复字符的最长子串

问题描述:

代码:

class Solution {
    public int lengthOfLongestSubstring(String s) {
       Set hx = new HashSet();
       int len=s.length();
       int r=0,ans=0;
       for(int i=0;i 
 思路:
 
 
 567. 字符串的排列
 
问题描述:
 
 
代码:
 
class Solution {
    public boolean checkInclusion(String s1, String s2) {
        int len1=s1.length(),len2=s2.length();
       int []cnt1=new int[26];int []cnt2=new int[26];
        if(len1>len2)
        return false;
        for(int i=0;i 
 思路:
 
 
代码2:
 
class Solution {
    public boolean checkInclusion(String s1, String s2) {
        int n = s1.length(), m = s2.length();
        if (n > m) {
            return false;
        }
        int[] cnt = new int[26];
        for (int i = 0; i < n; ++i) {
            --cnt[s1.charAt(i) - 'a'];
        }
        int left = 0;
        for (int right = 0; right < m; ++right) {
            int x = s2.charAt(right) - 'a';
            ++cnt[x];
            while (cnt[x] > 0) {
                --cnt[s2.charAt(left) - 'a'];
                ++left;
            }
            if (right - left + 1 == n) {
                return true;
            }
        }
        return false;
    }
}

 
思路2(双指针):