constructor [bahasa C++]

#include "stdio.h"
#include "stdlib.h"

class coba
{
      int _a, _b;   //private default
      
      public:
             coba(int a)      //constructor create
             {
                      _a = a;
                      
                      printf("nilai dari variabel a = %d\n\n", _a);
             };
             
             coba (int a, int b)    //constructor create
             {
                  _a = a;
                  _b = b;
                  
                  int c = _a + _b;
                  
                  printf("%d + %d = %d [ _a + _b = c]\n\n", _a, _b, c);
             };
};

int main()
{
    coba c1(5);
    coba c2(5,6);
    
    system("pause");
    return 0;
}