Truncate Sentence

给一个sentence, 里面没有前置和后置空格, 求前k个words的sentence.

class Solution {
    public String truncateSentence(String s, int k) {
        String[] strs = s.split(" ");
        StringBuilder sb = new StringBuilder();
        for(int i = 0 ; i < k && i < strs.length ; i ++) {
            sb.append(strs[i]+" ");
        }
        return sb.toString().trim();
    }
}