foo.cc: In function 'int main()':
foo.cc:7:24: warning: format '%c' expects argument of type 'char*', but argument 4 has type 'float*' [-Wformat=]
    7 |         scanf("*%f,%f,%c",&n1,&n2,&r);
      |                       ~^          ~~
      |                        |          |
      |                        char*      float*
      |                       %e
foo.cc:8:9: error: case label ''+'' not within a switch statement
    8 |         case'+';
      |         ^~~~
foo.cc:8:16: error: expected ':' before ';' token
    8 |         case'+';
      |                ^
      |                :
foo.cc:10:9: error: case label ''-'' not within a switch statement
   10 |         case'-';
      |         ^~~~
foo.cc:10:16: error: expected ':' before ';' token
   10 |         case'-';
      |                ^
      |                :
foo.cc:12:5: error: case label ''*'' not within a switch statement
   12 |     case'*';
      |     ^~~~
foo.cc:12:12: error: expected ':' before ';' token
   12 |     case'*';
      |            ^
      |            :
foo.cc:14:5: error: case label ''/'' not within a switch statement
   14 |     case'/';
      |     ^~~~
foo.cc:14:12: error: expected ':' before ';' token
   14 |     case'/';
      |            ^
      |            :
foo.cc:16:8: error: break statement not within loop or switch
   16 |        break;
      |        ^~~~~
foo.cc:6:14: warning: unused variable 'op' [-Wunused-variable]
    6 |         char op;
      |              ^~
foo.cc: At global scope:
foo.cc:18:7: error: expected constructor, destructor, or type conversion before '(' token
   18 | printf("&,2f",r);
      |       ^
foo.cc:19:1: error: expected unqualified-id before 'return'
   19 | return 0;
      | ^~~~~~

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