Compilare: user.cpp: In function ‘int main()’: user.cpp:554:32: warning: unused variable ‘index’ [-Wunused-variable] auto l = query.fi, index = query.se; ^ user.cpp:529:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("calafat.in", "r", stdin); ^ user.cpp:530:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("calafat.out", "w", stdout); ^ user.cpp:532:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ user.cpp:533:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] re (i, N) scanf("%d", A + i); ^ user.cpp:536:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &l, &r); ^