foo.cc: In function 'int main()':
foo.cc:12:15: warning: format '%s' expects argument of type 'char*', but argument 3 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   12 |     scanf("%d%s%s%s",&n,a,b,c);
      |              ~^
      |               |
      |               char*
foo.cc:12:17: warning: format '%s' expects argument of type 'char*', but argument 4 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   12 |     scanf("%d%s%s%s",&n,a,b,c);
      |                ~^
      |                 |
      |                 char*
foo.cc:12:19: warning: format '%s' expects argument of type 'char*', but argument 5 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   12 |     scanf("%d%s%s%s",&n,a,b,c);
      |                  ~^
      |                   |
      |                   char*
foo.cc:15:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   15 |         printf("%d\n",a);
      |                 ~^
      |                  |
      |                  int
foo.cc:19:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   19 |         printf("%d\n",b);
      |                 ~^
      |                  |
      |                  int
foo.cc:23:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::string' {aka 'std::__cxx11::basic_string<char>'} [-Wformat=]
   23 |         printf("%d\n",c);
      |                 ~^
      |                  |
      |                  int
foo.cc:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |     scanf("%d%s%s%s",&n,a,b,c);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~

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