Eroare de compilare: user.cpp:34:23: warning: missing terminating " character user.cpp:34: error: missing terminating " character user.cpp: In function ‘void back(int)’: user.cpp:23: warning: suggest explicit braces to avoid ambiguous ‘else’ user.cpp:27: error: ‘struct std::istream’ has no member named ‘close’ user.cpp:28: error: ‘struct std::ostream’ has no member named ‘close’ user.cpp: In function ‘int main()’: user.cpp:33: error: variable ‘std::ifstream cin’ has initializer but incomplete type user.cpp:35: error: variable ‘std::ofstream cout’ has initializer but incomplete type user.cpp:38: error: ‘system’ was not declared in this scope user.cpp:32: warning: unused variable ‘i’ user.cpp:32: warning: unused variable ‘j’ user.cpp:35: warning: unused variable ‘cout’