foo.cc:11:29: warning: character constant too long for its type
   11 |                         case'x=0 or y=0':
      |                             ^~~~~~~~~~~~
foo.cc:14:29: warning: character constant too long for its type
   14 |                         case'x,y>o':
      |                             ^~~~~~~
foo.cc:17:29: warning: character constant too long for its type
   17 |                         case'x<0,y>0':
      |                             ^~~~~~~~~
foo.cc:20:29: warning: character constant too long for its type
   20 |                         case'x,y<0':
      |                             ^~~~~~~
foo.cc:23:29: warning: character constant too long for its type
   23 |                         case'x>0,y<0':
      |                             ^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:8:18: warning: right operand of comma operator has no effect [-Wunused-value]
    8 |         cin>> x,y;
      |                  ^
foo.cc:9:16: warning: left operand of comma operator has no effect [-Wunused-value]
    9 |         switch(x,y)
      |                ^
foo.cc:23:25: error: duplicate case value
   23 |                         case'x>0,y<0':
      |                         ^~~~
foo.cc:20:25: note: previously used here
   20 |                         case'x,y<0':
      |                         ^~~~

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