foo.cc: In function 'int main()':
foo.cc:10:16: 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<tmp.size();i++)
      |               ~^~~~~~~~~~~
foo.cc:25:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |  for(int i=0;i<s.size();i++)
      |              ~^~~~~~~~~
foo.cc:40:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |  for(int i=0;i<s.size();i++)
      |              ~^~~~~~~~~
foo.cc:23:6: warning: unused variable 'num' [-Wunused-variable]
   23 |  int num;
      |      ^~~
foo.cc:36:16: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |  cout<<a<<":"<<b<<endl;
      |                ^
foo.cc:36:11: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |  cout<<a<<":"<<b<<endl;
      |           ^~~

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