151. Reverse Words in a String

Posted 2022-06-18 cznczai

class Solution 
          public String reverseWords(String s) 
         StringBuffer ans = new StringBuffer("");
         StringBuffer res = new StringBuffer("");
         for(int i = 0 ;i< s.length() ;i++) 
             while(i< s.length()&&s.charAt(i)==' ')
                 i++;                //找到i所对应的字符不是" "
             StringBuffer temp = new StringBuffer("");        //用stringBuffer 效率高 用string就超时了
             while(i< s.length()&&s.charAt(i)!=' ') 
                 temp.insert(0, s.charAt(i)) ;
                 i++;
             
             res.append( temp);res.append(" ");
             int x = res.length()-1;
             while(x>= 0&&res.charAt(x)==' ')                    //多加了几个空格 这里倒数找出非空格的位置 然后继续
                 x--;
             
             while(x>= 0) 
                 ans.append(res.charAt(x));
                 x--;
             
            
         return ans.toString();