Compilare: user.cpp: In function ‘int main()’: user.cpp:23:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < len && len - i + dq.size() > M; i++) { ^ user.cpp:27:78: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (!dq.empty() && dq.front() < v[i] && len - i + dq.size() > M) { ^ user.cpp:17:39: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d %s", &N, &M, v); ^