Compilare: main.cpp: In function 'void back()': main.cpp:11:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 11 | if(kit == p.size() && b % 2 == 1){ | ~~~~^~~~~~~~~~~ main.cpp:15:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 15 | if(kit == p.size() && b % 2 == 0){ | ~~~~^~~~~~~~~~~ main.cpp:19:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 19 | if(kit == p.size()){ | ~~~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:66:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 66 | for(int i = 0; i < sol.size(); i++) | ~~^~~~~~~~~~~~