Building a savings account program?

[JSkidds2294]

#include "stdafx.h"
#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;


int _tmain() {

// declare variables

int principal = 1000;
double rate = .03;
int years = 1; //counter
double balance = 0.0;

// Begin loop


do{
balance = principal * pow(1 + rate, years);
cout << "year " << years << ":" << endl;
cout << " $" << balance << endl;
years += 1; //update years counter

} while (years < 6);

system("pause");
return 0;
}


//This is the end of the initial program...

I need to modify the program to use annual interests rates of 3%, 4%, and 5%.

After that I need to modify the program to make it so the user enters the dollar amount of the deposit, the interest rate or rates, and the number of years.

I'm a design student at New England Tech but before we can go full design they want to make sure we know for sure if we want to be a designer or a programmer and so we need to take C++ classes which I suck at so any help would be appreciated.

[2kaud]

First, when posting code please use code tags to make the code readable. Go Advanced, select the code and then click '#'.

double rate = .03;

3% is really 3 / 100 which is .03. So you should be able to change the interest rate to 4%, 5% or any other required interest rate.

For the user to enter data from the keyboard in c++, the stream cin is usually used (as opposed to cout to display). For example

double amount;
cin >> amount;

will obtain the input from the user of type double and store it in the variable amount.

For more info about cin see http://www.cplusplus.com/reference/iostream/cin/

You might also like to look at these sites
http://www.cplusplus.com/doc/tutorial/
http://www.learncpp.com/

[VictorN]

#include "stdafx.h"
#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;


int _tmain() {

	// declare variables

	int principal = 1000;
	double rate = .03;
	int years = 1;       //counter
	double balance = 0.0;

	// Begin loop


	do{
		balance = principal * pow(1 + rate, years);
		cout << "year " << years << ":" << endl;
		cout << "   $" << balance << endl;
		years += 1;     //update years counter

	} while (years < 6);

	system("pause");
	return 0;
}

//This is the end of the initial program...

I need to modify the program to use annual interests rates of 3%, 4%, and 5%.

Fist you have to use Code tags. Otherwise your code is very hard to read/understand.
Second, what is the problem to "modify the program to use annual interests rates of 3%, 4%, and 5%"?
Third, about homework.

[JSkidds2294]

Sorry it was my first time posting on this site also I figured out the problem out before this thread became visible. I was also just asking for tips or examples not the HW done for me. Sorry for the confusion.

[JSkidds2294]

Also thank you to 2kaud for try to help.