Compilare: user.cpp: In function ‘int main()’: user.cpp:97:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tarc.in", "r", stdin); ^ user.cpp:98:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tarc.out", "w", stdout); ^ user.cpp:101:10: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp:105:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp:110:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccJh2j9K.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.