Compilare: main.cpp: In function 'int main()': main.cpp:23:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 23 | for(int p=0;p<ev.size();p++) | ~^~~~~~~~~~ main.cpp:27:16: 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 | while(j<ev.size()&&ev[j].first==ev[p].first) | ~^~~~~~~~~~