foo.cc: In function 'int main()':
foo.cc:8:19: error: expected primary-expression before '%' token
  scanf("%f,%f,%f",%a,&b,&c) ;
                   ^
foo.cc:12:7: error: expected ':' before 's'
       s=a+b;
       ^
foo.cc:15:7: error: expected ':' before 's'
       s=a-b;
       ^
foo.cc:18:7: error: expected ':' before 's'
       s=a*b;
       ^
foo.cc:21:7: error: expected ':' before 's'
       s=a/b;
       ^

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