swtich语句的用法

Question

switch语句为什么这个不能正常运行，学废了，大家帮忙看看

Answer 1

case 90-100这种写法是错误的

int n;
scanf("%d",&n);
n = n/10;
switch(n)
{
   case 10:
   case 9:
      printf("A\n");
      break;
   case 8:
      printf("B\n");
      break;
   case 7:
      printf("C\n");
      break;
    case 6:
      printf("D\n");
      break;
    default:
      printf("E\n");
      break;
}