Compilare: main.cpp: In function 'int main()': main.cpp:71:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 71 | for (int i = 0; i<ans.size(); i++) { | ~^~~~~~~~~~~ main.cpp:77:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 77 | for (int i = 0; i<ans.size()-1; i++) { | ~^~~~~~~~~~~~~