Compilare: user.cpp: In function ‘int main()’: user.cpp:35:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secventa.in","r",stdin); ^ user.cpp:36:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secventa.out","w",stdout); ^ user.cpp:37:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &n, &k); ^ user.cpp:38:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccSNFTiN.o: In function `main': user.cpp:(.text.startup+0x72): warning: the `gets' function is dangerous and should not be used.