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/***************************************************
Compound Interest

Write a program that reads an annual interest rate
and a term (number of years) from the user, and
computes the ammount of money you'd have after that
number of years at that interest rate, assuming you
make $100.00 payments into the account at the
beginning of each year.

The formula for interest is this:  If A is the
amount of money in your account at the beginning of
the year, and r is the annual interest rate, the
amount in your account at the end of the year is:

        A*(1.0 + r/100.0)

***************************************************/
#include "si204.h"

int main() {
  // Read interest rate
  fputs("Enter interest rate: ", stdout);
  double r = readnum(stdin);

  // Read number of years
  fputs("Enter number of years: ", stdout);
  int total_years = readnum(stdin);

  // INITIALIZATION FOR THE LOOP
  double T = 0.0; // We don't have any money yet
  int years = 0; // no years gone by yet

  // LOOP: COMPUTE total_years COMPOUNDING STEPS
  while (years < total_years) {
    // update T and years for one more year gone by
    T = (T + 100.0) * (1.0 + r/100.0);
    years = years + 1;
  }

  // Write out results
  fputs("Final amount is: $", stdout);
  writenum(T, stdout);
  fputs("\n", stdout);

  return 0;
}