/**
7. Suppose the interest rate on a loan goes up $.25\% $ points
each year. Write a function  {\em rate(double\& r)} that increments the
interest rate for the next year. Use this function in a program that
receives user input for the principal $P$, initial interest rate $i$ and the
loan period $n$ and prints out the total due. 
**/

#include<iostream>
using namespace std;

void rate(double&);

int main() {
  double principal, initial_rate,r;
  int n,loan_period;
  cout<<"Enter principal, initial_rate and loan_period(int, years), on one line separated by spaces"<<endl;
  cin>>principal>>initial_rate>>loan_period;
  r=initial_rate;
  n=1;
  do{
    principal += principal*r/100;
    rate(r);
    n++;
  } while(n<=loan_period);
  cout <<"The amount due is " <<principal<<endl;
}

void rate(double& r){
  r=r+0.25;
}