foo.cc: In function 'int main()':
foo.cc:28:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |     for(i=0;i<n.length();i++){
      |             ~^~~~~~~~~~~
foo.cc:37:15: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
   37 |     }printf("%d",t);
      |              ~^  ~
      |               |  |
      |               |  long long int
      |               int
      |              %lld
foo.cc:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |     scanf("%d",&m);
      |     ~~~~~^~~~~~~~~
foo.cc:13:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |         scanf("%d%d",&x,&y);
      |         ~~~~~^~~~~~~~~~~~~~

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