Chapter 4 Exercises

//Exercise 4.13 - Gas Mileage Calculator
//I was trying to make a function for the while loop which would call in the mileage function but I couldn't get it to work
#include <iostream>
using namespace std;

double miles{0}, gallons{0}, totalMiles{0}, totalGallons{0}, mpg{0};


double mileage(double m, double g) {
    mpg = m / g;
    return mpg;
}

int main()
{
    cout << "Enter miles driven (-1 to quit): ";
    cin >> miles;
    while (miles != -1) {

        totalMiles += miles;
        cout << "Enter gallons used: ";
        cin >> gallons;
        totalGallons += gallons;
        cout << "MPG this trip: ";
        cout << mileage(miles, gallons) << endl;
        cout << "Total MPG: " << mileage(totalMiles, totalGallons) << endl;
        cout << "\n";
        cout << "Enter miles driven (-1 to quit): ";
        cin >> miles;
    }
}



//Exercise 4.17 - Find the Largest
//This program finds the largest of 10
#include <iostream>

using namespace std;

void salesCalc(int counter, int number, int largest) {
    while (counter <= 10) {
        cout << "please input salesperson " << counter << "'s sales total: ";
        cin >> number;
            if (number > largest) {
                largest = number;
            }
        counter++;
    }
    cout << "Largest sales total: " << largest << endl;
}

int main()
{
    int i{1}, number{0}, largest{0};

    salesCalc(i, number, largest);
}


//Exercise 4.26 - Square of Asterisks
//I did this 2 different ways because I initially created a single function
//So I recreated it using 3 much neater functions.

#include <iostream>
using namespace std;

void solidRow(int rowLength){
    int i{1};
    while (i <= rowLength) {
        cout << "*";
        i++;
        }
    cout << endl;
}

void hollowRow(int rowLength) {
    int i{2};
    cout << "*";
    while (i < rowLength) {
        cout << " ";
        i++;
    }
    cout << "*" << endl;
}

void multiFunctionSquare(int rowLength) {
    int i{2};
    solidRow(rowLength);
    while (i < rowLength) {
        hollowRow(rowLength);
        i++;
    }
    if (rowLength != 1) {
        solidRow(rowLength);
    }
}

void singleFunctionSquare(int length) {
    int i{1};
    int j{0};
        while (i <= length) {
            while ((i == 1) && (j < length)) {
                cout << "*";
                j++;
            }
        cout << endl;
        i++;
        j = 0;
            while ((i > 1) && (i < length)) {
                if (j == 0) {
                    cout << "*";
                    j++;
                }
                else if((j > 0) && (j < (length - 1))){
                    cout << " ";
                    j++;
                }
                else if (j == (length - 1)) {
                    cout << "*" << endl;
                    j = 0;
                    i++;
                }
            }
            while ((i == length) && (j < length)) {
            cout << "*";
            j++;
            }
    cout << endl;
    i++;
    }

}

int main()
{
    int length{0};
    cout << "Please enter a number:";
    cin >> length;

    cout << "Multi Function Square:" << endl;
    multiFunctionSquare(length);
    cout << "Single Function Square:" << endl;
    singleFunctionSquare(length);
}



// exercise 4.35 - Factorial and e calculations

#include <iostream>
#include <iomanip>
#include <cmath>

using namespace std;

double factorial(double input) {
    int i{1};
    double j{input};
    while (i < j) {
        input *= i;
        i++;
    }
    return input;
}
double eulers() {
    int i{1};
    double e{1};

    while (i < 20) {
        e += (1 / factorial(i));
        i++;
    }
    return e;
}

double ePowers(double x){
    double i{1};
    double e{1};

    while (i < 20) {
        e += (pow(x, i) / factorial(i));
        i++;
    }
    return e;
}
int main()
{
    int num{0};
    double x{0};

    cout << "Please enter a number you would like the factorial for: ";
    cin >> num;
    cout << "Factorial is " << factorial(num) << endl;

    cout << "Please enter the terms of e to display:";
    cin >> num;

    cout << "e is: " << setprecision(num) << eulers() << endl;

    cout << "Please enter the power of e:";
    cin >> x;

    cout << "enter the terms in e^x to display: ";
    cin >> num;

    cout << "e to the power of " << x << " displayed to " << num
     << " terms is: " << setprecision(num) << ePowers(x) << endl;
}

//Exercise 4.36 Account Class Modification
// Fig. 3.8: Account.h
// Account class with name and balance data members, and a
// constructor and deposit function that each perform validation.
#include <string>
#include <iomanip>

class Account {
public:
   // Account constructor with two parameters
   Account(std::string accountName, int initialBalance)
      : name{accountName} { // assign accountName to data member name

      // validate that the initialBalance is greater than 0; if not,
      // data member balance keeps its default initial value of 0
      if (initialBalance > 0) { // if the initialBalance is valid
         balance = initialBalance; // assign it to data member balance
      }
   }

   // function that deposits (adds) only a valid amount to the balance
   void deposit(int depositAmount) {
      if (depositAmount > 0) { // if the depositAmount is valid
         balance = balance + depositAmount; // add it to the balance
      }
   }

   // function returns the account balance
   double getBalance() const {
      return balance;
   }

   // function that sets the name
   void setName(std::string accountName) {
      name = accountName;
   }

   // function that returns the name
   std::string getName() const {
      return name;
   }

private:
   std::string name; // account name data member
   double balance{0}; // data member with default initial value
}; // end class Account


/**************************************************************************
 * (C) Copyright 1992-2017 by Deitel & Associates, Inc. and               *
 * Pearson Education, Inc. All Rights Reserved.                           *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 *************************************************************************/



//exercise 4.36 - Account Class Modification Main File


// Fig. 3.9: AccountTest.cpp
// Displaying and updating Account balances.
#include <iostream>
#include <iomanip>
#include "Account.h"


using namespace std;

void displayAccount (Account accountToDisplay) {
 cout << "Account: " << accountToDisplay.getName()
 << " balance is $" << accountToDisplay.getBalance() << endl;
 }

int main()
{
    cout << setprecision(2) << fixed;
   Account account1{"Jane Green", 50};
   Account account2{"John Blue", -7};


   // display initial balance of each object
   displayAccount(account1);
   displayAccount(account2);

   cout << "\n\nEnter deposit amount for account1: "; // prompt
   int depositAmount;
   cin >> depositAmount; // obtain user input
   cout << "adding " << depositAmount << " to account1 balance";
   account1.deposit(depositAmount); // add to account1's balance

   // display balances
   displayAccount(account1);
   displayAccount(account2);

   cout << "\n\nEnter deposit amount for account2: "; // prompt
   cin >> depositAmount; // obtain user input
   cout << "adding " << depositAmount << " to account2 balance";
   account2.deposit(depositAmount); // add to account2 balance

   // display balances
   displayAccount(account1);
   displayAccount(account2);
}

/**************************************************************************
 * (C) Copyright 1992-2017 by Deitel & Associates, Inc. and               *
 * Pearson Education, Inc. All Rights Reserved.                           *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 *************************************************************************/