namespace TheBasicCalculator {
public static void Main(string[] args) {
Console.WriteLine("Welcome to Basic Calculator");
Console.WriteLine("===========================");
Console.WriteLine("For one number, you can type as many numbers as you want.");
Console.WriteLine("For instance, you can type 5+8 as one number.");
Console.WriteLine("Don\'t add spaces between numbers and signs.");
Console.WriteLine("1. +");
Console.WriteLine("2. -");
Console.WriteLine("3. x");
Console.WriteLine("4. /");
Console.WriteLine("5. 1/x");
Console.WriteLine("6. x^2");
Console.WriteLine("7. sqrt(x)");
Console.WriteLine("8. %");
Console.WriteLine("9. CE");
Console.WriteLine("10. C");
Console.WriteLine("11. ±");
Console.WriteLine("12. Exit");
Console.WriteLine("selection > ");
bool isUsingCalculator = true;
while (isUsingCalculator) {
operation = Console.ReadLine();
isUsingCalculator = true;
Console.WriteLine("First number or problem: ");
firstToAdd = Console.ReadLine();
Console.WriteLine(firstToAdd);
double firstNumberToAdd = Convert.ToDouble(firstToAdd);
Console.WriteLine("Second number or problem: ");
secondToAdd = Console.ReadLine();
Console.WriteLine(secondToAdd);
double secondNumberToAdd = Convert.ToDouble(secondToAdd);
double sum = firstNumberToAdd + secondNumberToAdd;
if (Convert.ToDouble(firstNumberToAdd + secondNumberToAdd) == Convert.ToInt32(firstNumberToAdd + secondNumberToAdd)) {
Console.WriteLine(Convert.ToInt32(firstNumberToAdd+secondNumberToAdd) + "");
Console.WriteLine((firstNumberToAdd+secondNumberToAdd) + "");
Console.WriteLine("N/A");
Console.WriteLine("Welcome to Basic Calculator");
Console.WriteLine("===========================");
Console.WriteLine("For one number, you can type as many numbers as you want.");
Console.WriteLine("For instance, you can type 5+8 as one number.");
Console.WriteLine("Don\'t add spaces between numbers and signs.");
Console.WriteLine("1. +");
Console.WriteLine("2. -");
Console.WriteLine("3. x");
Console.WriteLine("4. /");
Console.WriteLine("5. 1/x");
Console.WriteLine("6. x^2");
Console.WriteLine("7. sqrt(x)");
Console.WriteLine("8. %");
Console.WriteLine("9. CE");
Console.WriteLine("10. C");
Console.WriteLine("11. ±");
Console.WriteLine("12. Exit");
Console.WriteLine("selection > ");
isUsingCalculator = true;
Console.WriteLine("First number or problem: ");
firstToSubtract = Console.ReadLine();
Console.WriteLine(firstToSubtract);
double firstNumberToSubtract = Convert.ToDouble(firstToSubtract);
Console.WriteLine("Second number or problem: ");
secondToSubtract = Console.ReadLine();
Console.WriteLine(secondToSubtract);
double secondNumberToSubtract = Convert.ToDouble(secondToSubtract);
double difference = firstNumberToSubtract - secondNumberToSubtract;
if (firstNumberToSubtract - secondNumberToSubtract == Convert.ToInt32(firstNumberToSubtract - secondNumberToSubtract)) {
Console.WriteLine(Convert.ToInt32(firstNumberToSubtract - secondNumberToSubtract) + "");
Console.WriteLine((firstNumberToSubtract - secondNumberToSubtract) + "");
Console.WriteLine("No ter");
Console.WriteLine("Welcome to Basic Calculator");
Console.WriteLine("===========================");
Console.WriteLine("For one number, you can type as many numbers as you want.");
Console.WriteLine("For instance, you can type 5+8 as one number.");
Console.WriteLine("Don\'t add spaces between numbers and signs.");
Console.WriteLine("1. +");
Console.WriteLine("2. -");
Console.WriteLine("3. x");
Console.WriteLine("4. /");
Console.WriteLine("5. 1/x");
Console.WriteLine("6. x^2");
Console.WriteLine("7. sqrt(x)");
Console.WriteLine("8. %");
Console.WriteLine("9. CE");
Console.WriteLine("10. C");
Console.WriteLine("11. ±");
Console.WriteLine("12. Exit");
Console.WriteLine("selection > ");
isUsingCalculator = true;
Console.WriteLine("First number or problem: ");
firstToMultiply = Console.ReadLine();
Console.WriteLine(firstToMultiply);
double firstNumberToMultiply = Convert.ToDouble(firstToMultiply);
Console.WriteLine("Second number or problem: ");
secondToMultiply = Console.ReadLine();
Console.WriteLine(secondToMultiply);
double secondNumberToMultiply = Convert.ToDouble(secondToMultiply);
double product = firstNumberToMultiply * secondNumberToMultiply;
if (firstNumberToMultiply * secondNumberToMultiply == Convert.ToInt32(firstNumberToMultiply * secondNumberToMultiply)) {
Console.WriteLine("" + Convert.ToInt32(firstNumberToMultiply * secondNumberToMultiply));
Console.WriteLine((firstNumberToMultiply * secondNumberToMultiply) + "");
Console.WriteLine("N/A");
Console.WriteLine("Welcome to Basic Calculator");
Console.WriteLine("===========================");
Console.WriteLine("For one number, you can type as many numbers as you want.");
Console.WriteLine("For instance, you can type 5+8 as one number.");
Console.WriteLine("Don\'t add spaces between numbers and signs.");
Console.WriteLine("1. +");
Console.WriteLine("2. -");
Console.WriteLine("3. x");
Console.WriteLine("4. /");
Console.WriteLine("5. 1/x");
Console.WriteLine("6. x^2");
Console.WriteLine("7. sqrt(x)");
Console.WriteLine("8. %");
Console.WriteLine("9. CE");
Console.WriteLine("10. C");
Console.WriteLine("11. ±");
Console.WriteLine("12. Exit");
Console.WriteLine("selection > ");
isUsingCalculator = true;
Console.WriteLine("First number or problem: ");
firstToDivide = Console.ReadLine();
Console.WriteLine(firstToDivide);
double firstNumberToDivide = Convert.ToDouble(firstToDivide);
Console.WriteLine("Second number or problem: ");
secondToDivide = Console.ReadLine();
Console.WriteLine(secondToDivide);
double secondNumberToDivide = Convert.ToDouble(secondToDivide);
double quotient = firstNumberToDivide / secondNumberToDivide;
if (firstNumberToDivide % secondNumberToDivide == 0) {
Console.WriteLine(Convert.ToDouble(firstNumberToDivide / secondNumberToDivide) + "" );
Console.WriteLine(Convert.ToDouble(firstNumberToDivide/secondNumberToDivide) + "");
Console.WriteLine("N/A");
Console.WriteLine("Welcome to Basic Calculator");
Console.WriteLine("===========================");
Console.WriteLine("For one number, you can type as many numbers as you want.");
Console.WriteLine("For instance, you can type 5+8 as one number.");
Console.WriteLine("Don\'t add spaces between numbers and signs.");
Console.WriteLine("1. +");
Console.WriteLine("2. -");
Console.WriteLine("3. x");
Console.WriteLine("4. /");
Console.WriteLine("5. 1/x");
Console.WriteLine("6. x^2");
Console.WriteLine("7. sqrt(x)");
Console.WriteLine("8. %");
Console.WriteLine("9. CE");
Console.WriteLine("10. C");
Console.WriteLine("11. ±");
Console.WriteLine("12. Exit");
Console.WriteLine("selection > ");
isUsingCalculator = true;
string numberToFindReciprocalOf;
double reciprocalOfThisNumber;
Console.WriteLine("Type the number or problem: ");
numberToFindReciprocalOf = Console.ReadLine();
Console.WriteLine("1/" + numberToFindReciprocalOf);
reciprocalOfThisNumber = (1 / Convert.ToDouble(numberToFindReciprocalOf));
Console.WriteLine(reciprocalOfThisNumber + "" );
Console.WriteLine("N/A");
isUsingCalculator = true;
Console.WriteLine("Type the number or problem: ");
numberSquared = Console.ReadLine();
double theNumberSquared = Convert.ToDouble(numberSquared);
if (Convert.ToDouble(theNumberSquared * theNumberSquared) == Convert.ToInt32(theNumberSquared * theNumberSquared)) {
Console.WriteLine(Convert.ToInt32(theNumberSquared * theNumberSquared) + "");
Console.WriteLine((theNumberSquared * theNumberSquared) + "");
Console.WriteLine("N/A");
isUsingCalculator = true;
Console.WriteLine("Type the number or problem: ");
string numberTimesNumber = Console.ReadLine();
double theNumberTimesTheNumber = Convert.ToDouble(numberTimesNumber);
if (Convert.ToDouble(Math.Sqrt(theNumberTimesTheNumber)) == Convert.ToInt32(Math.Sqrt(theNumberTimesTheNumber))) {
Console.WriteLine(Convert.ToInt32(Math.Sqrt(theNumberTimesTheNumber)) + "");
Console.WriteLine(Convert.ToDouble(Math.Sqrt(theNumberTimesTheNumber)) + "");
Console.WriteLine("N/A");
isUsingCalculator = true;
Console.WriteLine("First number or problem: ");
dividend = Console.ReadLine();
Console.WriteLine(dividend);
double firstNumberForModulus = Convert.ToDouble(dividend);
Console.WriteLine("Second number or problem: ");
divisor = Console.ReadLine();
Console.WriteLine(divisor);
double secondNumberForModulus = Convert.ToDouble(divisor);
double remainder = firstNumberForModulus % secondNumberForModulus;
if(Convert.ToDouble(firstNumberForModulus%secondNumberForModulus) == Convert.ToInt32(firstNumberForModulus%secondNumberForModulus)) {
Console.WriteLine(Convert.ToInt32(firstNumberForModulus%secondNumberForModulus) + "");
Console.WriteLine(Convert.ToDouble(firstNumberForModulus%secondNumberForModulus) + "");
Console.WriteLine("N/A");
isUsingCalculator = true;
Console.WriteLine("Cleared last");
isUsingCalculator = true;
Console.WriteLine("Cleared all");
isUsingCalculator = true;
Console.WriteLine("1: +, 2: -, 3: *, 4: /, 5: %");
string firstNumberOrProblem;
string plusMinusMultiplyDivideModulus;
string secondNumberOrProblem;
Console.WriteLine("First number or problem:");
firstNumberOrProblem = Console.ReadLine();
Console.WriteLine("Sign: type 1 for +, 2 for -, 3 for *, 4 for /, and 5 for %.");
plusMinusMultiplyDivideModulus = Console.ReadLine();
Console.WriteLine("Second number or problem: ");
secondNumberOrProblem = Console.ReadLine();
string fullProblem = Convert.ToString(firstNumberOrProblem) + plusMinusMultiplyDivideModulus + Convert.ToString(secondNumberOrProblem);
double theFirstNumberOrProblem = Convert.ToDouble(firstNumberOrProblem);
double theSecondNumberOrProblem = Convert.ToDouble(secondNumberOrProblem);
if (Convert.ToInt32(plusMinusMultiplyDivideModulus) == 1) {
if (Convert.ToDouble(theFirstNumberOrProblem+theSecondNumberOrProblem) == Convert.ToInt32(theFirstNumberOrProblem+theSecondNumberOrProblem)) {
Console.WriteLine((Convert.ToInt32(theFirstNumberOrProblem+theSecondNumberOrProblem) / -1) + "");
Console.WriteLine(((theFirstNumberOrProblem+theSecondNumberOrProblem) / -1) + "");
Console.WriteLine("N/A");
} else if (Convert.ToInt32(plusMinusMultiplyDivideModulus) == 2) {
if (Convert.ToDouble(theFirstNumberOrProblem-theSecondNumberOrProblem) == Convert.ToInt32(theFirstNumberOrProblem-theSecondNumberOrProblem)) {
Console.WriteLine((Convert.ToInt32(theFirstNumberOrProblem-theSecondNumberOrProblem) / -1) + "");
Console.WriteLine(((theFirstNumberOrProblem-theSecondNumberOrProblem) / -1) + " ");
Console.WriteLine("N/A");
} else if (Convert.ToInt32(plusMinusMultiplyDivideModulus) == 3) {
if (Convert.ToDouble(theFirstNumberOrProblem*theSecondNumberOrProblem) == Convert.ToInt32(theFirstNumberOrProblem*theSecondNumberOrProblem)) {
Console.WriteLine((Convert.ToInt32(theFirstNumberOrProblem*theSecondNumberOrProblem) / -1) + "");
Console.WriteLine(((theFirstNumberOrProblem*theSecondNumberOrProblem) / -1) + " ");
Console.WriteLine("N/A");
} else if (Convert.ToInt32(plusMinusMultiplyDivideModulus) == 4) {
if (Convert.ToDouble(theFirstNumberOrProblem/theSecondNumberOrProblem) == Convert.ToInt32(theFirstNumberOrProblem/theSecondNumberOrProblem)) {
Console.WriteLine((Convert.ToInt32(theFirstNumberOrProblem/theSecondNumberOrProblem) / -1) + "");
Console.WriteLine(((theFirstNumberOrProblem/theSecondNumberOrProblem) / -1) + "");
Console.WriteLine("N/A");
} else if (Convert.ToInt32(plusMinusMultiplyDivideModulus) == 5) {
if (Convert.ToDouble(theFirstNumberOrProblem%theSecondNumberOrProblem) == Convert.ToInt32(theFirstNumberOrProblem%theSecondNumberOrProblem)) {
Convert.ToInt32(theFirstNumberOrProblem%theSecondNumberOrProblem);
Console.WriteLine(((theFirstNumberOrProblem%theSecondNumberOrProblem) / -1) + "");
Convert.ToDouble(theFirstNumberOrProblem%theSecondNumberOrProblem);
Console.WriteLine(((theFirstNumberOrProblem%theSecondNumberOrProblem) / -1) + "");
Console.WriteLine("N/A");
Console.WriteLine("N/A");
Console.WriteLine("Exit");
isUsingCalculator = false;
Console.WriteLine("Invalid option");
Console.WriteLine("Invalid option");