virtual - Reusing functions in C++ -

i having trouble writing code in class inherits class reuses function of class in 1 of functions
file pessoa.h:

#ifndef pessoa_h #define pessoa_h #include "data.h" #include <string>  class pessoa {    string nome;    data aniversario; public:    pessoa(string tnome, data taniversario){nome = tnome; aniversario =       taniversario;} pessoa(){}; int aniversario(data data_atual);  virtual void imprime(); ~pessoa();  };  #endif 

file universitario.h:

#ifndef uni_h #define uni_h #include "pessoa.h" #include "data.h"  class universitario: public pessoa {     int matricula;     data ingresso;   public:     universitario(int tmatricula, data tingresso, string nome, data     aniversario):      pessoa(nome, aniversario) {matricula = tmatricula; ingresso = tingresso;}     universitario(){};     void imprime();     ~universitario();   };  #endif 

function imprime() definition pessoa.cpp:

void pessoa::imprime() {         cout << "nome: " << this->nome << endl;  } 

function imprime() definition uni.cpp:

void universitario::imprime() {     this->imprime();     cout << "matricula: " << this->matricula << endl;     ingresso.imprimed();  } 

the error this:

undefined symbols architecture x86_64:   "pessoa::~pessoa()", referenced from:       universitario::~universitario() in main-0c1624.o       universitario::universitario(int, data,     std::__1::basic_string<char, std::__1::char_traits<char>,     std::__1::allocator<char> >, data) in main-0c1624.o   "typeinfo pessoa", referenced from:       typeinfo universitario in main-0c1624.o   "vtable pessoa", referenced from:       pessoa::pessoa(std::__1::basic_string<char,    std::__1::char_traits<char>, std::__1::allocator<char> >, data) in main-   0c1624.o   note: missing vtable means first non-inline virtual member function has no definition. ld: symbol(s) not found architecture x86_64 clang: error: linker command failed exit code 1 (use -v see invocation) 

i guessing error either on virtual or this.

"pessoa::~pessoa()", referenced from: 

you need implement destructor. declared it.

instead of this:

~pessoa(); 

try this:

~pessoa() {} 

same holds true universitario destructor.