foo.c: In function 'main':
foo.c:7:11: error: expected ';' before 'b'
    7 | else a=a+b
      |           ^
      |           ;
    8 |         b=a-b;
      |         ~  
foo.c:12:11: error: expected ';' before 'c'
   12 | else a=a+c
      |           ^
      |           ;
   13 |         c=a-c;
      |         ~  
foo.c:17:11: error: expected ';' before 'c'
   17 | else b=b+c
      |           ^
      |           ;
   18 |         c=b-c;
      |         ~  

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