foo.cc: In function 'int main()':
foo.cc:16:17: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   16 |  if(m.size()-i-1<=n) {
      |     ~~~~~~~~~~~~^~~
foo.cc:18:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |   for(int j=0; j<n-m.size()+i+1; j++) cout<<'0';
      |                ~^~~~~~~~~~~~~~~

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