【LeeCode】49. 字母异位词分组 -- TODO

【题目描述】

给你一个字符串数组，请你将 字母异位词 组合在一起。可以按任意顺序返回结果列表。

字母异位词 是由重新排列源单词的字母得到的一个新单词，所有源单词中的字母通常恰好只用一次。

​​​https://leetcode.cn/problems/group-anagrams/?favorite=2cktkvj​​​

【示例】

import java.util.*;
import java.util.stream.Collectors;
// 2022-12-19

class Solution {
    List<List<String>> res = new ArrayList<>();
    public List<List<String>> groupAnagrams(String[] strs) {

        // "eat","tea","tan","ate","nat","bat"
        List<String> strings = Arrays.asList(strs);
        int[] dp = new int[strings.size()];
        for (String x : strs){
            List<String> list1 = fullStr(x);
            List<String> list = new ArrayList<>();
            Set<String> set = new HashSet<>();
            for (int i = 0, len = strings.size(); i < len; i++) {
                String tmp = strings.get(i);
                if (list1.contains(tmp) && dp[i] == 0){
                    set.add(tmp);
                    dp[i] = 1;
                }
            }
            // System.out.println("set: " + set);
            for (String xx: set){
                if (xx.length() != 0){
                    list.add(xx);
                }
            }
            System.out.println(list);
            res.add(list);
        }

        return res;
    }

    public List<String> fullStr(String x) {
        List<String> list = new ArrayList<>();
        list.add(x.charAt(0)+"");
        for (int i = 1; i < x.length(); i++){
            char c = x.charAt(i);
            List<String> list2 = new ArrayList<>();
            for (String s : list){
                list2.add(s+c);  // eat
                list2.add(c+s);  // tea
                for (int j = 1; j < s.length(); j++){  // e + t + a
                    String tmp = s.substring(0, j) + c + s.substring(j);
                    list2.add(tmp);
                }
            }
            list = list2;
        }
        // System.out.println(list);
        return list;
    }
}
public class Main{
    public static void main(String[] args) {
        String[] str = {"eat","tea","tan","ate","nat","bat"};
        new Solution().groupAnagrams(str);    // 输出： 3   [1, 5], [1, 4], [1]

        // new Solution().fullStr("eat");
    }
}