Sams Teach Yourself C in 21 Days

LISTINGT&R 6 mortgage.c. The mortgage calculator

1: /* Calculates loan/mortgage payments. */

2:

3: #include <stdio.h>

4: #include <math.h>

5: #include <stdlib.h>

6:

7: int main( void )

8: {

9: float principal, rate, payment;

10: int term;

11: char ch;

12:

13: while (1)

14: {

15: /* Get loan data */

16: puts(“\nEnter the loan amount: “);

17: scanf(“%f”, &principal);

18: puts(“\nEnter the annual interest rate: “);

19: scanf(“%f”, &rate);

20: /* Adjust for percent. */

21: rate /= 100;

22: /* Adjust for monthly interest rate. */

23: rate /= 12;

24:

25: puts(“\nEnter the loan duration in months: “);

26: scanf(“%d”, &term);

27: payment = (principal * rate) / (1 - pow((1 + rate), -term));

28: printf(“Your monthly payment will be $%.2f.\n”, payment);

29:

30: puts(“Do another (y or n)?”);

31: do

32: {

33: ch = getchar();

34: } while (ch != ‘n’ && ch != ‘y’);

35:

36: if (ch == ‘n’)

37: break;

38: }

39: return 0;

40: }

This program assumes a standard loan, such as a typical fixed-rate car or home

loan. The payment is calculated using the following standard financial formula:

payment= (P* R) / ( 1 - (1 + R)^(-T))

562 Type & Run 6

INPUT

ANALYSIS

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