Compilare: main.cpp: In function 'int main()': main.cpp:81:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 81 | for(int f = 0 ; f < m.size() ; f ++) | ~~^~~~~~~~~~ main.cpp:82:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 82 | for(int e = f + 1 ; e < m.size() ; e ++) | ~~^~~~~~~~~~