/in/foo.c:2:6: warning: return type of 'main' is not 'int' [-Wmain]
 void main()
      ^~~~
/in/foo.c: In function 'main':
/in/foo.c:12:5: error: case label not within a switch statement
     case 1: printf("k");
     ^~~~
/in/foo.c:13:5: error: case label not within a switch statement
     case 2: printf("w");
     ^~~~
/in/foo.c:24:5: error: case label not within a switch statement
     case 1: printf("k");
     ^~~~
/in/foo.c:25:5: error: case label not within a switch statement
     case 2: printf("w");
     ^~~~
/in/foo.c:38:5: error: case label not within a switch statement
     case 1: printf("k");
     ^~~~
/in/foo.c:39:5: error: case label not within a switch statement
     case 2: printf("w");
     ^~~~
/in/foo.c:5:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=0;i<9;i++)
  ^~~
/in/foo.c:44:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   k=1;
   ^