Compilare: user.cpp: In function ‘int range(int)’: user.cpp:49:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < sets.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:79:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numar2.in", "r", stdin); ^ user.cpp:80:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numar2.out", "w", stdout); ^ user.cpp:81:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:83:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &A[i]); ^