Compilare: main.cpp: In function 'int main()': main.cpp:148:23: 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:155:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (pos_out < out.size() && v[out[pos_out].second].x2 <= i){ ~~~~~~~~^~~~~~~~~~~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:15:29: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^