tickets.cpp: In function 'long long int find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:27:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
27 | for(int i = 0; i < v.size(); i++) {
| ~~^~~~~~~~~~
tickets.cpp:28:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
28 | if(i < v.size() / 2) ans -= v[i].f, cn[v[i].s]--;
| ~~^~~~~~~~~~~~~~
tickets.cpp:42:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
42 | for(int i = 0; i < x.size(); i++) {
| ~~^~~~~~~~~~
tickets.cpp:44:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
44 | if(i < x.size() / 2) {
| ~~^~~~~~~~~~~~~~