message.cpp: In function 'int get(std::vector<bool>&, int)':
message.cpp:13:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |   if(ind<v.size()) return v[ind];
      |      ~~~^~~~~~~~~
message.cpp: In function 'void send_message(std::vector<bool>, std::vector<bool>)':
message.cpp:19:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |     for(int i=0;i<positions.size();i++)
      |                 ~^~~~~~~~~~~~~~~~~
message.cpp:28:23: warning: comparison of integer expressions of different signedness: 'std::vector<bool>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   28 |     if(message.size() < free_bits) {
      |        ~~~~~~~~~~~~~~~^~~~~~~~~~~
message.cpp:41:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |     for(int i=0;i<positions.size()-1;i++) {
      |                 ~^~~~~~~~~~~~~~~~~~~
message.cpp:53:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |     while(msg_ind < msg.size())
      |           ~~~~~~~~^~~~~~~~~~~~
message.cpp: In function 'std::vector<bool> receive_message(std::vector<std::vector<bool> >)':
message.cpp:84:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<bool> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |   for(int i=5+30;i<received_bits.size();i++) {
      |                  ~^~~~~~~~~~~~~~~~~~~~~
message.cpp:94:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |     for(int i=5;i<rcv.size();i++) ret.push_back(rcv[i]);
      |                 ~^~~~~~~~~~~
message.cpp:100:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |     for(int i=11;i<rcv.size();i++) ret.push_back(rcv[i]);
      |                  ~^~~~~~~~~~~
message.cpp:101:22: warning: comparison of integer expressions of different signedness: 'std::vector<bool>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  101 |     while(ret.size() > len) ret.pop_back();
      |           ~~~~~~~~~~~^~~~~