I gave some thought to what was mention and this is what i came up with ->
Code:
#include <iostream>
#include <iomanip>
using namespace std;

const double INT = 0.10;

int main()
{
	int years=0, x=0;
	double P0=0, Px=0, P1=0, interest=0;

	cout << fixed << showpoint;
	cout << setprecision(2);

	cout << "Program that reads an initial amount and computes "
		 << "the total in the account on your sixtieth birthday." << endl << endl;

	cout << "Enter the initial amount of the account -> ";
	cin >> P0;

	Px = P0;

	cout << "Enter the amount of years the account remain untouch -> ";
	cin >> years;
	
	cout << endl << endl;
	cout << "The initial investment was $" << P0 << " . The total amount accumulated after "
		 << years <<" years, if $" << P0 << " is allowed to compound with an interest of 10.00%,"
		 << "comes to $";
	
	for (x = 0; x != years; x++)
		{
			P1 = P0 + ( P0 * INT);

			while (P0 < P1)
				P0 = P1;
		}
	cout << P1 <<'.' << endl << endl;
	cout << "The total amount accumulated after " << years << " (years + 1) years," 
		<<" if $" << Px << " is allowed to compound with an interest of 10%, comes to $";
	
	years += 1;

	for (x = 0; x != years; x++)
		{
			if (x == years - 1)
				interest += (Px * INT);	
			P1 = Px + ( Px * INT);

			while (Px < P1)
				Px = P1;
		}

	cout << P1 << " ." << endl << endl;
	cout << "The interest earned during this year is $" << interest
		<< ".If interest is withdrawn each year thereafter, my income is $"
		 << (P0 / 12) << " per month." << endl << endl;

		return 0;
}
I was wondering it anyone can make any comment or mention anyways of improving the program to make it more efficient.
THANKZ