????def?reverse_sentence(s):
????????if?not?s?or?s[::-1]?==?s:
????????????return?s
????????return?'?'.join([i?for?i?in?list(s.split())[::-1]])

public class fanzhuan {
    public static void reverse(char[] input,int start,int end){

        char temp=0;
        while(start<end){
            temp=input[start];
            input[start]=input[end];
            input[end]=temp;
            start++;
            end--;
        }
    }

    public static void rotateWord(char[] input){
        int end=input.length-1;
        boolean flag=false;
        if ((input[end]>='a'&&input[end]<='z')||(input[end]>='A'&&input[end]<='Z')){

        }
        else {

            flag=true;
            end--;

        }
        reverse(input,0,end);
        int l=-1;
        int r=-1;
        for (int i=0;i<=end;i++){
            if (input[i]!=' '){
                l=i==0||input[i-1]==' '?i:l;
                r=i==end||input[i+1]==' '?i:r;
            }
            if (l!=-1&&r!=-1){

                reverse(input,l,r);
                l=-1;
                r=-1;
            }
        }



    }

    public static void main(String[] args) {
        String test="hello word!";
        char[] test1=test.toCharArray();
        rotateWord(test1);
        String test2=String.valueOf(test1);
        System.out.println(test2);
    }
}

@Test
	public void test7(){
		String a = "Hello how are you!";
		StringBuffer sb = new StringBuffer();
		char last = a.charAt(a.length()-1);
		//Unicode 編碼并不只是為某個字符簡單定義了一個編碼，而且還將其進行了歸類。 
		//這里24表示標點符號這一類型
		if(Character.getType(last)==24){
			a = a.substring(0, a.length()-1);
		}
		String[] splits = a.split("\\s");
		for (int i = splits.length-1; i >= 0; i--) {
			sb.append(splits[i]+(i==0?"":" "));
		}
		sb.append(last);
		System.out.println(sb.toString());
	}