foo.cc: In function 'int main()':
foo.cc:12:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         while(i<a.size()&&j<b.size()) ans+=(a[i++]-'0')+(b[j++]-'0');
      |               ~^~~~~~~~~
foo.cc:12:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         while(i<a.size()&&j<b.size()) ans+=(a[i++]-'0')+(b[j++]-'0');
      |                           ~^~~~~~~~~
foo.cc:13:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |         while(i<a.size()) ans+=a[i++]-'0';
      |               ~^~~~~~~~~
foo.cc:14:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |         while(j<b.size()) ans+=b[j++]-'0';
      |               ~^~~~~~~~~

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