Compilare: user.cpp: In function ‘int main()’: user.cpp:101:33: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘std::basic_string<char>::iterator {aka __gnu_cxx::__normal_iterator<char*, std::basic_string<char> >}’ [-Wformat=] printf("%s\n",it.begin()); ^ user.cpp:94:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp:95:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bilete.in" , "r", stdin); ^ user.cpp:96:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bilete.out", "w", stdout); ^ user.cpp:97:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&k); ^