Compilare: user.cpp: In function ‘int main()’: user.cpp:13:25: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘long long int’ [-Wformat=] printf("%d",(k+1)*(k+1)); ^ user.cpp: In function ‘void openIOFiles()’: user.cpp:5:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prim.in","r",stdin); ^ user.cpp:6:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prim.out","w",stdout); ^ user.cpp: In function ‘int main()’: user.cpp:12:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld",&k); ^