Compilare: main.cpp: In function 'int main()': main.cpp:98:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (pos_in < in.size() && v[in[pos_in].second].x <= i + dx - 1){ ~~~~~~~^~~~~~~~~~~ main.cpp:105:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (pos_out < out.size() && v[out[pos_out].second].x2 <= i){ ~~~~~~~~^~~~~~~~~~~~