public int lengthOfLastWord(String s) {
    if(s.length()==0)return 0;
	char va[]=s.toCharArray();
	int index=va.length-1;
	while (index>=0&&va[index]==' ') {
		index--;
	}
	int i;
	for( i=index;i>=0;i--)
	{
		if(va[i]==' ')
		{
			break;
		}
	}
	 
	 return index-i;
   }