This program shows pre-defined values.

#include <iostream.h>
#include <conio.h>

void main()
{
  clrscr();
  int x = 10;
  float y = 10.1;
  char z = 'a';
  cout << "x = " << x << endl;
  cout << "y = " << y << endl;
  cout << "z = " << z << endl;
  getch();
}

output:
x = 10
y = 10.1
z = a