How long does it take (in months) to accumulate a debt of €100 starting with a debt of €50 and being charged with 2% each months?

02.Balance.cpp

// 02.Balance.cpp
// from Savitch
// How long does it take (in months) to accumulate a debt
// of €100 starting with a debt of €50 and being charged with
// 2% each months?

#include <iostream>
using namespace std;
// consts
const float STARTING_DEBT = 50.0;
const float MAXDEBT = 100.0;
const float INTRATE= 2;

int main( )
{
    double balance = STARTING_DEBT;
    int count = 0;
    cout << "This program tells you how long it takes\n"
         << "to accumulate a debt of " << MAXDEBT
         << ", starting with\n"
         << "an initial balance of " << STARTING_DEBT
         << " owed.\n"
         << "The interest rate is " << INTRATE
         << "% per month.\n";

    while (balance < MAXDEBT) {
        balance = balance + INTRATE/100.0 * balance;
        count++;
    }

    cout << "After " << count << " months, your balance\
 due will be €" << balance << endl;
    return 0;
}