【leetcode】Anagrams
- 题目
- Given an array of strings, return all groups of strings that are anagrams.
- 首先简单介绍一下Anagram（回文构词法）。Anagrams是指由颠倒字母顺序组成的单词，比如"tea"会变成"eat"。
For example:
Input:["tea","and","ate","eat"]
Output: ["tea","ate","eat"]
- 解题思路
- 定义一个Arraylist ar存储所有字符串排序后的字符串
- ar:["aet", "aet", "aet", "adn"]
- 定义一个list[strs.length]标记字符串是否要被输出，1：被输出
- 定义一个tmp，记录同样字符串的个数，大于1被输出
- 两层循环，两两比较，相同的话，tmp+1，相应list位标记为1，如果从第i位算起，后面都没有与第i个字符串相同的话，第i位list重新标记为0.
- list标记位为：1 1 1 0
- 将相应位的string数组输出即可
- 代码
package leetcode;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
/**
* Given an array of strings, return all groups of strings that are anagrams.
*
* Note: All inputs will be in lower-case.
*/
public class Anagrams {
public static void main(String[] args) {
String[] strs = new String[] { "tea", "eat", "ate", "and" };
Anagrams anagrams = new Anagrams();
ArrayList result = new ArrayList<>();
result = anagrams.anagrams(strs);
System.out.println("result's length is " + result.size());
System.out.print("result is " + "[ ");
Iterator iterator = result.iterator();
while (iterator.hasNext()) {
Object object = (Object) iterator.next();
System.out.print("\"" + object + "\"" + "," + " ");
}
System.out.println("]");
}
public ArrayList<String> anagrams(String[] strs) {
ArrayList<String> ret = new ArrayList<String>();
ArrayList<String> ar = new ArrayList<String>();
for (String s : strs) {
char[] c = s.toCharArray();
Arrays.sort(c);
ar.add(new String(c));
}
int[] list = new int[strs.length];
int tmp = 0;
for (int i = 0; i < ar.size(); i++) {
if (list[i] == 0) {
list[i] = 1;
tmp = 1;
for (int j = i + 1; j < ar.size(); j++) {
if (list[j] == 0 && ar.get(i).equals(ar.get(j))) {
list[j] = 1;
tmp++;
}
}
if (tmp == 1) {
list[i] = 0;
}
}
}
for (int i = 0; i < list.length; i++) {
if (list[i] == 1)
ret.add(strs[i]);
}
return ret;
}
}
