foo.cc: In function 'int main()':
foo.cc:12:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |  for(int i=0;i<s.size();i++)
      |              ~^~~~~~~~~
foo.cc:8:6: warning: unused variable 'flag' [-Wunused-variable]
    8 |  int flag=0;
      |      ^~~~
foo.cc:9:6: warning: unused variable 'cnt' [-Wunused-variable]
    9 |  int cnt=0,bnt=0;
      |      ^~~
foo.cc:9:12: warning: unused variable 'bnt' [-Wunused-variable]
    9 |  int cnt=0,bnt=0;
      |            ^~~

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