/in/foo.cc: In function 'int main()':
/in/foo.cc:107:91: warning: comparison of integer expressions of different signedness: 'std::size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  107 |                 if ((boat1[0] == 0) && flag[j] && (boat1[0] != boat2[0]) && (tmp2.count() <= m))
      |                                                                              ~~~~~~~~~~~~~^~~~