foo.cc: In function 'int trans(std::string, std::string)':
foo.cc:15:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         for(int i = 0; i < s2.size(); ++i){
      |                        ~~^~~~~~~~~~~
foo.cc:17:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                         while(j < s1.size() && s1[j] != '1'){
      |                               ~~^~~~~~~~~~~
foo.cc:13:13: warning: unused variable 'i' [-Wunused-variable]
   13 |         int i = 0, j = 0;
      |             ^
foo.cc: In function 'int main()':
foo.cc:36:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |         for(int i = 0; i < s1.size(); ++i){
      |                        ~~^~~~~~~~~~~
foo.cc:64:17: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   64 |         cout << ans << endl;
      |                 ^~~

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