Compilare: user.cpp: In function ‘void Cit(str&)’: user.cpp:82:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (sir + 1); ^ user.cpp: In function ‘int main()’: user.cpp:89:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arbsort.in", "r", stdin); ^ user.cpp:90:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("arbsort.out", "w", stdout); ^ user.cpp:92:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d\n", &N); ^ /tmp/cckc6Ocf.o: In function `Cit(str&)': user.cpp:(.text+0x21e): warning: the `gets' function is dangerous and should not be used.