#define MORTGAGE 100000.0				// Initial balance
#define RATE 0.09 							// 9% annual rate 
#define MONTHS 180						// Maximum number of months
#define PAYMAX 1200						// Maximum monthly payment

2lp_main()
{
continuous Pymt,Bal[MONTHS+1];

	Bal[0] == MORTGAGE;
	Pymt <= PAYMAX;
	and(int k=0;k<MONTHS;k++) 
		if Bal[k] == 0.0;
		then {	// mortgage can be paid off
			printf("Make %d payments of $%.2f\n",k,Pymt);
			break;
		}		// else make another payment
		else Bal[k+1] == (1 + RATE/12)*Bal[k] - Pymt;
}
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