Check If String Is a Prefix of Array
给一个字符串s和一个字符串组, 求这个字符串组所组成的prefix字符串有没有s.
class Solution {
public boolean isPrefixString(String s, String[] words) {
Set<String> set = new HashSet<>();
int n = words.length;
StringBuilder sb = new StringBuilder();
for(int i = 0; i < n; i++)
{
sb.append(words[i]);
set.add(sb.toString());
}
return set.contains(s);
}
}