题解 | #牛牛的串联子串游戏#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param s string字符串 
     * @param words string字符串一维数组 
     * @return int整型一维数组
     */
    public int[] findSubstring (String s, String[] words) {
        // write code here
        List<Integer> indexL = new ArrayList<>();
        int subStringLength = words.length * words[0].length();
        for (int i=0; i <= (s.length() - subStringLength); i++){
            String pStr = s.substring(i, i+subStringLength);
            if (checkIfValidStr(pStr, words)){
                indexL.add(i);
            }
        }
        int[] results = indexL.stream().mapToInt(Integer::valueOf).toArray();
        return results;
    }
    public static boolean checkIfValidStr(String s, String[] words){
        for (String w : words){
            s = s.replaceFirst(w, "");
        }
        if (s.length() == 0){
            return true;
        }
        return false;
    }
}