Compilare: main.cpp: In function 'int main()': main.cpp:162:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2; i < ports.size(); ++i) { ~~^~~~~~~~~~~~~~ main.cpp:180:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ports.size(); ++i) { ~~^~~~~~~~~~~~~~ main.cpp:194:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ports.size(); ++i) { ~~^~~~~~~~~~~~~~ main.cpp:226:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2; i < ports.size(); ++i) { ~~^~~~~~~~~~~~~~ main.cpp:234:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ports.size(); ++i) { ~~^~~~~~~~~~~~~~