foo.cc: In function 'int main()':
foo.cc:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for(int i=0;i<a.size();i++)
      |                     ~^~~~~~~~~
foo.cc:13:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |         for(int i=0;i<b.size();i++)
      |                     ~^~~~~~~~~
foo.cc:16:19: warning: unused variable 'flag' [-Wunused-variable]
   16 |         int pos=0,flag=0,cnt=0;
      |                   ^~~~

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