Compilare: user.cpp: In function ‘int main()’: user.cpp:48:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (fi*2+1<h.size() && (h[fi].a>h[fi*2].a || h[fi].a>h[fi*2+1].a)) ^ user.cpp:53:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (fi*2==h.size()-1 && h[fi].a>h[fi*2].a) swap(h[fi*2],h[fi]); ^