输入月份和日期给出对应星座

#include<stdioh>
void main()
{
int a,b,c;
scanf("%d%d",&a,&b);
c=a100+b;
switch(c)
{
case (c>=121&&c<=220):printf("%a月%b日为宝瓶座\n",a,b);
case (c>=221&&c<=320):printf("%d月%d日为双鱼座\n",a,b);
case (c>=321&&c<=420):printf("%d月%d日为白羊座\n",a,b);
case (c>=421&&c<=520):printf("%d月%d日为金牛座\n",a,b);
case (c>=521&&c<=620):printf("%d月%d日为双子座\n",a,b);
case (c>=621&&c<=722):printf("%d月%d日为巨蟹座\n",a,b);
case (c>=723&&c<=822):printf("%d月%d日为狮子座\n",a,b);
case (c>=823&&c<=922):printf("%d月%d日为处女座\n",a,b);
case (c>=923&&c<=1022):printf("%d月%d日为天秤座\n",a,b);
case (c>=1023&&c<=1122):printf("%d月%d日为天蝎座\n",a,b);
case (c>=1023&&c<=1222):printf("%d月%d日为人马座\n",a,b);
case (c>=1223&&c<=1231):printf("%d月%d日为摩羯座\n",a,b);
case (c>=101&&c<=120):printf("%d月%d日为双鱼座\n",a,b);
}
}

很简单的