/in/foo.cc: In function 'int main()':
/in/foo.cc:26:31: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   26 |                 if (c1.size() > n / 2) {
      |                     ~~~~~~~~~~^~~~~~~
/in/foo.cc:32:43: warning: comparison of integer expressions of different signedness: 'long long int' and 'long long unsigned int' [-Wsign-compare]
   32 |                         for (int i = 1; i <= c1.size() - n / 2; i ++) {
      |                                         ~~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:36:31: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   36 |                 if (c2.size() > n / 2) {
      |                     ~~~~~~~~~~^~~~~~~
/in/foo.cc:42:43: warning: comparison of integer expressions of different signedness: 'long long int' and 'long long unsigned int' [-Wsign-compare]
   42 |                         for (int i = 1; i <= c2.size() - n / 2; i ++) {
      |                                         ~~^~~~~~~~~~~~~~~~~~~~