Compilare: main.cpp:1:9: warning: #pragma once in main file #pragma once ^~~~ main.cpp: In member function 'void PairingHeap::build(const std::vector<int>&)': main.cpp:64:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) { ~~^~~~~~~~~~ main.cpp: In member function 'void PairingHeap::show()': main.cpp:96:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < parents[i].size(); j++) { ~~^~~~~~~~~~~~~~~~~~~