Compilare: user.cpp: In function ‘int main()’: user.cpp:29:17: warning: unused variable ‘value’ [-Wunused-variable] int ok = 1, value = N; ^ user.cpp:24:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("towerx.in" ,"r", stdin ); ^ user.cpp:25:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("towerx.out","w", stdout); ^ user.cpp:27:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^