Compilare: user.cpp: In function ‘int main()’: user.cpp:63:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pq.size() == k) { ~~~~~~~~~~^~~~ user.cpp:52:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &n); ^ user.cpp:54:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &k); ^ user.cpp:57:55: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &v[i].first, &v[i].second); ^