class Demo{public static void main (String[]args){int x = 6;if (x>12 || x=3&&x=6&&x=9&&

class Demo{public static void main (String[]args){int x = 6;if (x>12 || x=3&&x=6&&x=9&&
class Demo
{
public static void main (String[]args)
{
int x = 6;
if (x>12 || x=3&&x=6&&x=9&&

class Demo{public static void main (String[]args){int x = 6;if (x>12 || x=3&&x=6&&x=9&&
class Demo
{
 public static void main (String[]args)
 {
  int x = 6;
  if (x>12 || x<1)
  System.out.println(x+"月份不存在");//分号打成了中文字符,去掉大括号
  else if (x>=3&&x<=5)
  System.out.println(x+"春季");
  else if (x>=6&&x<=8)
  System.out.println(x+"夏季");
  else if (x>=9&&x<=11)//应该是else if
  System.out.println(x+"秋季");
  else //else后面不跟判断语句
  System.out.println(x+"冬季");
  }
 
}

错误好多.