Compilare: user.cpp: In member function ‘int Heap::insert(int)’: user.cpp:16:2: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In member function ‘void Heap::pushdown(int)’: user.cpp:30:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (p * 2 + 1 >= v.size()) { ^ user.cpp:36:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (s+1 < v.size() && v[s+1] < v[s]) { ^ user.cpp: In member function ‘int Heap::at(int)’: user.cpp:68:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (v.size() < p) { ^ user.cpp: In member function ‘void Heap::print()’: user.cpp:76:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<v.size(); ++i) { ^