判断：两个数x、y的正负性。

要求：不可以使用比较运算符，即"<",">","<=",">=","==","!="。





有多组数据，每组数据占一行，每一行两个数x，y。

x、y保证在int范围内。


输出 每组数据输出占一行。

如果两个数是一正一负，输出"Signs are opposite"


如果是同为正或同为负，输出"Signs are not opposot"


如果无法确定，输出"Signs can't be sure"


输出不包括引号


样例输入

1 1 -1 1

样例输出

Signs are not opposot Signs are opposite



#include<stdio.h> 
int main() {
  int x,y; 
  while(scanf("%d %d",&x,&y) == 2) {
    if(x*y>0) 
      printf("Signs are not opposot\n"); 
      else if(x*y<0) 
        printf("Signs are opposite\n");
          else printf("Signs can't be sure\n"); 
  }
  return 0; 
}