foo.cc:9:29: warning: character constant too long for its type
    9 |                         case'x=0 or y=0':
      |                             ^~~~~~~~~~~~
foo.cc:12:29: warning: character constant too long for its type
   12 |                         case'x,y>o':
      |                             ^~~~~~~
foo.cc:15:29: warning: character constant too long for its type
   15 |                         case'x<0,y>0':
      |                             ^~~~~~~~~
foo.cc:18:29: warning: character constant too long for its type
   18 |                         case'x,y<0':
      |                             ^~~~~~~
foo.cc:21:29: warning: character constant too long for its type
   21 |                         case'x>0,y<0':
      |                             ^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:6:9: error: 'cin' was not declared in this scope
    6 |         cin x,y;
      |         ^~~
foo.cc:7:16: warning: left operand of comma operator has no effect [-Wunused-value]
    7 |         switch(x,y)
      |                ^
foo.cc:21:25: error: duplicate case value
   21 |                         case'x>0,y<0':
      |                         ^~~~
foo.cc:18:25: note: previously used here
   18 |                         case'x,y<0':
      |                         ^~~~

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