/in/foo.cc: In function 'int main()':
/in/foo.cc:30:31: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   30 |                 if (c1.size() > n / 2) {
      |                     ~~~~~~~~~~^~~~~~~
/in/foo.cc:36:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |                         for (int i = 1; i <= c1.size() - n / 2; i ++) {
      |                                         ~~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:40:31: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   40 |                 if (c2.size() > n / 2) {
      |                     ~~~~~~~~~~^~~~~~~
/in/foo.cc:46:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |                         for (int i = 1; i <= c2.size() - n / 2; i ++) {
      |                                         ~~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:50:31: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   50 |                 if (c3.size() > n / 2) {
      |                     ~~~~~~~~~~^~~~~~~
/in/foo.cc:56:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |                         for (int i = 1; i <= c3.size() - n / 2; i ++) {
      |                                         ~~^~~~~~~~~~~~~~~~~~~~