Compilare: user.cpp: In function ‘int main()’: user.cpp:54:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp:52:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ghicit.in","r",stdin); ^ user.cpp:53:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ghicit.out","w",stdout); ^ user.cpp:55:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/ccJwYGLv.o: In function `main': user.cpp:(.text.startup+0x53): warning: the `gets' function is dangerous and should not be used.