Eroare de compilare: user.cpp:3:20: error: vector.h: No such file or directory user.cpp:4:19: error: stack.h: No such file or directory user.cpp:12: error: expected constructor, destructor, or type conversion before ‘<’ token user.cpp: In function ‘void df(long int)’: user.cpp:23: error: ‘a’ was not declared in this scope user.cpp: In function ‘int main()’: user.cpp:41: error: ‘a’ was not declared in this scope user.cpp:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result