Compilare: main.cpp: In function 'int main()': main.cpp:92:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 92 | for (int i = 1; i < ctc.size(); i++) | ~~^~~~~~~~~~~~ main.cpp:121:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 121 | for (int i = 1; i < ctc.size(); i++) | ~~^~~~~~~~~~~~ main.cpp:146:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 146 | for (int i = 1; i < ctc.size(); i++) | ~~^~~~~~~~~~~~