foo.cc: In function 'int main()':
foo.cc:2:99: warning: format '%d' expects argument of type 'int', but argument 2 has type 'double' [-Wformat=]
    2 | using namespace std;int main(){double a,b;char c;scanf("%lf,%lf,%c",&a,&b,&c);if(c=='+')printf("%2d",a+b);else if(c=='-') cout<<a-b; else if(c=='*') cout<<a*b;else cout<<a/b;return 0;}
      |                                                                                                 ~~^  ~~~
      |                                                                                                   |   |
      |                                                                                                   int double
      |                                                                                                 %2f
foo.cc:2:55: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    2 | using namespace std;int main(){double a,b;char c;scanf("%lf,%lf,%c",&a,&b,&c);if(c=='+')printf("%2d",a+b);else if(c=='-') cout<<a-b; else if(c=='*') cout<<a*b;else cout<<a/b;return 0;}
      |                                                  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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