Compilare: user.cpp: In function ‘void solve()’: user.cpp:23:10: warning: unused variable ‘j’ [-Wunused-variable] int i , j ; ^ user.cpp: In function ‘int main()’: user.cpp:52:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "password1.in" , "r" , stdin ) ; ^ user.cpp:53:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ( "password1.out" , "w" , stdout ) ; ^