/in/foo.cc: In function 'int main()':
/in/foo.cc:91:25: warning: value computed is not used [-Wunused-value]
   91 |                 boat[j] == 1;
/in/foo.cc:106:86: warning: comparison of integer expressions of different signedness: 'std::size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  106 |                 if (boat1[0] == 0 && flag[j] && boat1[0] != boat2[0] && tmp2.count() <= m)
      |                                                                         ~~~~~~~~~~~~~^~~~