题解 | #单词拆分(一)#

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 dic string字符串一维数组 
     * @return bool布尔型
     */
    public boolean wordDiv (String s, String[] dic) {
        List<String> list =  Arrays.asList(dic);
        HashSet<String> set = new HashSet<>(list);
        boolean[] dp = new boolean[s.length() + 1];
        dp[0] = true;
        for (int i = 1; i <= s.length(); i++) {
            for (int j = 0; j < i; j++) {
                if (dp[j] && set.contains(s.substring(j, i))){
                    dp[i] = true;
                }
            }
        }
        return dp[s.length()];
    }
}