foo.c: In function 'main':
foo.c:5:8: warning: missing terminating " character
    5 | printf("%d,x+y);
      |        ^
foo.c:5:8: error: missing terminating " character
    5 | printf("%d,x+y);
      |        ^~~~~~~~~
foo.c:6:1: error: expected expression before 'return'
    6 | return 0;
      | ^~~~~~
foo.c:6:10: error: expected ';' before '}' token
    6 | return 0;
      |          ^
      |          ;
    7 | }
      | ~         
foo.c:4:7: warning: unused variable 'y' [-Wunused-variable]
    4 | int x,y;
      |       ^
foo.c:4:5: warning: unused variable 'x' [-Wunused-variable]
    4 | int x,y;
      |     ^

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