Notes

#include <iostream>
#include <iomanip>
using namespace std;

int main()
{
int x;
int y;
int xt = 0;
int yt = 0;
cout << "Enter miles driven (-1 to quit): ";
cin >> x;
while (x != -1)
{
cout << "Enter gallons used: ";
cin >> y;
xt += x;
yt += y;
cout << "MPG this trip: " << setprecision(6) << fixed << static_cast<double>(x) / y << endl;
cout << "Total MPG: " << setprecision(6) << fixed << static_cast<double>(xt) / yt << endl;
cout << "Enter miles driven (-1 to quit): ";
cin >> x;
}
}

---

#include <iostream>
using namespace std;

int main()
{
int a;
double b;
double c;
double d;
double e;
cout << "Enter account number (or -1 to quit): ";
cin >> a;
while (a != -1)
{
cout << "Enter beginning balance: ";
cin >> b;
cout << "Enter total charges: ";
cin >> c;
cout << "Enter total credits: ";
cin >> d;
cout << "Enter credit limit: ";
cin >> e;

double f = b + c - d;

cout << "New balance is " << f << endl;

if (f > e)
{
cout << "Account: " << a << endl;
cout << "Credit Limit: " << e << endl;
cout << "Balance: " << f << endl;
cout << "Credit Limit Exceeded." << endl;
}
cout << endl;
cout << "Enter Account Number (or -1 to quit): ";
cin >> a;
}
}