C++の宿題 現在の年齢を返すメンバ関数Age

Age.cpp

#include <iostream>
#include <iomanip>
#include <string.h>
#include <time.h>

using namespace std;

class Date {
  private:
    int year;
    int month;
    int day;

  public:
    Date(int y = 1, int m = 1, int d = 1) {
      year = y; month = m; day = d;
    }   

    int Year(void)  const { return (year); }
    int Month(void) const { return (month); }
    int Day(void)   const { return (day); }
};

class Build {
  private:
    char  name[20];
    int   height;
    int   weight;
    Date  birth;
  public:
    Build(char* n, int y, int m, int d, int h, int w); 
    char* Name(void) { return (name); }
    int Height(void) { return (height); }
    int Weight(void) { return (weight); }
    int Age(void);
};

Build::Build (char* n, int y, int m, int d, int h, int w) : birth(y, m, d)
{
  strncpy(name, n, 20);
  height = h;
  weight = w;
}

int Build::Age (void)
{
  time_t now;
  struct tm* local;
  time(&now);
  local = localtime(&now);

  long int age = 0;
  age += (local->tm_year + 1900 - birth.Year())  * 10000;
  age += (local->tm_mon  + 1    - birth.Month()) * 100;
  age += local->tm_mday         - birth.Day();

  return (age/10000);
}

int main(void)
{
  char name[20] = "tdkn";
  Build man(name, 1992, 9, 2, 173, 65);
  cout << man.Age() << "歳\n";

  return (0);
}