Language: C++

#include<stdio.h>

int main(){
  int x,y;
  scanf("%d%d",&x,&y);
  
  switch(x){
    case 1:
    case 3:
    case 5:
    case 7:
    case 8:
    case 10:
    case 12: int xi=1; break;
    case 4:
    case 6:
    case 9:
    case 11: int xi=2; break;
    case 2: int xi=3; break;
  }
  
  switch(y){
    case 1:
    case 3:
    case 5:
    case 7:
    case 8:
    case 10:
    case 12: int yi=1; break;
    case 4:
    case 6:
    case 9:
    case 11: int yi=2; break;
    case 2: int yi=3; break;
  }
  if(xi==yi) printf("Yes");
  else printf("No");
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:15:10: error: jump to case label
   15 |     case 4:
      |          ^
a.cc:14:18: note:   crosses initialization of 'int xi'
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:16:10: error: jump to case label
   16 |     case 6:
      |          ^
a.cc:14:18: note:   crosses initialization of 'int xi'
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:17:10: error: jump to case label
   17 |     case 9:
      |          ^
a.cc:14:18: note:   crosses initialization of 'int xi'
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:18:10: error: jump to case label
   18 |     case 11: int xi=2; break;
      |          ^~
a.cc:14:18: note:   crosses initialization of 'int xi'
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:18:18: error: redeclaration of 'int xi'
   18 |     case 11: int xi=2; break;
      |                  ^~
a.cc:14:18: note: 'int xi' previously declared here
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:19:10: error: jump to case label
   19 |     case 2: int xi=3; break;
      |          ^
a.cc:14:18: note:   crosses initialization of 'int xi'
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:19:17: error: redeclaration of 'int xi'
   19 |     case 2: int xi=3; break;
      |                 ^~
a.cc:14:18: note: 'int xi' previously declared here
   14 |     case 12: int xi=1; break;
      |                  ^~
a.cc:30:10: error: jump to case label
   30 |     case 4:
      |          ^
a.cc:29:18: note:   crosses initialization of 'int yi'
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:31:10: error: jump to case label
   31 |     case 6:
      |          ^
a.cc:29:18: note:   crosses initialization of 'int yi'
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:32:10: error: jump to case label
   32 |     case 9:
      |          ^
a.cc:29:18: note:   crosses initialization of 'int yi'
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:33:10: error: jump to case label
   33 |     case 11: int yi=2; break;
      |          ^~
a.cc:29:18: note:   crosses initialization of 'int yi'
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:33:18: error: redeclaration of 'int yi'
   33 |     case 11: int yi=2; break;
      |                  ^~
a.cc:29:18: note: 'int yi' previously declared here
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:34:10: error: jump to case label
   34 |     case 2: int yi=3; break;
      |          ^
a.cc:29:18: note:   crosses initialization of 'int yi'
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:34:17: error: redeclaration of 'int yi'
   34 |     case 2: int yi=3; break;
      |                 ^~
a.cc:29:18: note: 'int yi' previously declared here
   29 |     case 12: int yi=1; break;
      |                  ^~
a.cc:36:6: error: 'xi' was not declared in this scope; did you mean 'x'?
   36 |   if(xi==yi) printf("Yes");
      |      ^~
      |      x
a.cc:36:10: error: 'yi' was not declared in this scope; did you mean 'y'?
   36 |   if(xi==yi) printf("Yes");
      |          ^~
      |          y