package leetcode.array;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

/**

* @ClassName FindCommonCharacters

* @Description 查找常用字符 https://leetcode-cn.com/problems/find-common-characters/

* @Author changxuan

* @Date 2020/10/14 下午8:19

**/

public class FindCommonCharacters {

public static void main(String[] args) {

System.out.println((byte)('a'));

String[] test = {"bella","label","roller"};

commonChars(test)

.stream().forEach(s -> System.out.println(s));

}

/**

* 哈希

* @param A

* @return

*/

public static List<String> commonChars(String[] A) {

List<String> res = new ArrayList<>();

if (A.length == 1 || A.length == 0) return Arrays.asList(A);

int[] hash = new int[26];

char[] firstChars = A[0].toCharArray();

for (int i = 0; i < firstChars.length; i++) {

hash[firstChars[i] - 'a']++;

}

for (int i = 1; i < A.length; i++) {

int[] othersHash = new int[26];

for (int j = 0; j < A[i].length(); j++) {

othersHash[A[i].toCharArray()[j] - 'a']++;

}

for (int k = 0; k < 26; k++) {

hash[k] = Math.min(hash[k], othersHash[k]);

}

}

for (int i = 0; i < 26; i++) {

while (hash[i] !=0) {

res.add(String.valueOf((char)('a'+i)));

hash[i]--;

}

}

return res;

}

}