Compilare: user.cpp: In function ‘int main()’: user.cpp:13:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sosete.in","r",stdin); ^ user.cpp:14:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s %s\n",a+1,b+1); ^ user.cpp:23:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sosete.out","w",stdout);f=(f-2)*2; ^ user.cpp:80:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sosete.out","w",stdout); ^ user.cpp:67:10: warning: ‘i’ may be used uninitialized in this function [-Wmaybe-uninitialized] int i; ^