using System; using System.Collections.Generic; using System.Globalization; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; namespace MyAppSTD2018 { class Program { static void Main(string[] args) { // Shortcuts Ctrl+. | Ctrl+r,r | cw \t\t | Ctrl+k,d | Ctrl+k,c | Ctrl+k,u // I. Types have: name (e.g. int), size, default value // II. Variables have: name (A-Za-z_0-9 all utf-8, can't start with 0-9, can't be a keyword), type, value // built-in types: //1. integer (default = 0) byte myByte = 23; // unsigned 8-bis (0 to 255) default = 0 sbyte mySByte = -128; // signed 8-bit (-128 to 127) default = 0 short myShort = -1000; // signed 16-bit (-32,768 to 32,767) ushort myUshort = 2000; // unsigned 16-bit (0 to 65,535) int myVar = 4; // signed 32-bit (-2,147,483,648 to 2,147,483,647) int myVar2 = 5; // signed 32-bit (-2,147,483,648 to 2,147,483,647) int sum = myVar + myVar2; // signed 32-bit (-2,147,483,648 to 2,147,483,647) uint myUint = 12000U; // unsigned 32-bit (0 to 4, 294, 967, 295) sum = 0xA8F1; // hexadecimal literal sum = 0XA8F1; // hexadecimal literal long myLong = 42432L;// signed 64-bit (-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807) ulong myUlong = 23423423U; // unsigned 64-bit (0 to 18,446,744,073,709,551,615) ulong maxIntValue = UInt64.MaxValue; Console.WriteLine(maxIntValue); // 18446744073709551615 // Check if there is overflow and throw an exception //checked //{ // int maxInt = int.MaxValue; // maxInt = maxInt + 1; // Console.WriteLine(maxInt); //} // if there is no check we will get wrong result -2147483648 // BigInteger myBigInt = 3213213; // No limits // 2. Real (default 0.0 for F/f D/d M/m) float myFloat = 4.566F; // signed 32-bit (±1.5e-45 to ±3.4e38) up to 7 symbols/digits myFloat = 67.8E35f; // litteral with "E/e" double myDouble = 34.56d; // signed 64-bit (±5.0e-324 to ±1.7e+308) up to 15-16 symbols/digits myDouble = -3.4e-10d; decimal myDecimal = 23.45M; // signed 128-bit (±1.0e-28 to ±7.9e28) precission 28-29 symbols/digits, closest to 0 ±1.0e-28, decimal floating-point arithmetic // Declare some variables float floatPI = 3.141592653589793238f; double doublePI = 3.141592653589793238; // Print the results on the console Console.WriteLine("Float PI is: " + floatPI); // Float PI is: 3.141593 only 7 digits Console.WriteLine("Double PI is: " + doublePI); // Double PI is: 3.14159265358979 16 digits decimal decimalPI = 3.14159265358979323846m; Console.WriteLine(decimalPI); // 3.14159265358979323846 // 3. Char char myFirstLetter = 'S'; Console.WriteLine((int)myFirstLetter); char symbol = (char)5; char myChar = '\u0065'; Console.WriteLine(myChar); myChar = '\uffff'; Console.WriteLine(myChar); // escaping char myEscape = '\n'; // \n \t \r \' \\ \" \uXXXX // 4. String (default null) Reference, value in the heap string myName = "Stoyan Cheresharov"; string path = @"D:\CamtasiaVideos"; // instead of D:\\CamtasiaVideos Console.WriteLine($"The Path is {path}"); //StringBuilder text = new StringBuilder(); //foreach (char symbol in list) // { // text.Append(symbol); //} // 5. Bool (default false) bool myBool = true; // false | true // 6. Object (default null) Reference, value in the heap Object myObject = 3; Nullable i1 = null; int? i2 = i1; // typeof() // Console.WriteLine(typeof(i1)); // error // Used to obtain the System.Type object for a type. A typeof expression takes the following form: System.Type type = typeof(int); int i = 0; type = i.GetType(); Console.WriteLine(type); // sizeof - Used to obtain the size in bytes for an unmanaged type. Console.WriteLine(sizeof(sbyte)); // 1 // Unmanaged types include: // The simple types that are listed in the following table: // Expression Constant value //sizeof(sbyte) 1 //sizeof(byte) 1 //sizeof(short) 2 //sizeof(ushort) 2 //sizeof(int) 4 //sizeof(uint) 4 //sizeof(long) 8 //sizeof(ulong) 8 //sizeof(char) 2(Unicode) //sizeof(float) 4 //sizeof(double) 8 //sizeof(decimal) 16 //sizeof(bool) 1 Console.WriteLine("Hello World! The sum is " + sum); Console.WriteLine("-----------------------"); Console.WriteLine((char)65); Console.WriteLine((int)'D'); Console.WriteLine('\u0065'); int? myVanya = null; Console.WriteLine("Vanya is " + myVanya.ToString() + " years old!"); Console.WriteLine(sizeof(long)); int myDesiInt = 10; // double myDesiDouble = 1.2; int myDesiDouble = 3; Console.WriteLine("Desi " + ((double)myDesiInt / myDesiDouble)); // Console.WriteLine("Desi " + ((myDesiInt / myDesiDouble)); // Ctrl+r,r - refactoring/replace a name/string // Not possible //int? implicitConvertInt = 0; //if (implicitConvertInt) { // Can not implicitly convert type int to bool //} //Object implicitConverToObj = null; //if (implicitConverToObj) { // Can not implicitly convert type Obj to bool //} myDesiInt++; Console.WriteLine(myDesiInt); Console.WriteLine((myDesiInt > 18) ? "You are an adult" : "You are young"); byte myTest = 1; Console.WriteLine(myTest); Console.WriteLine(myTest << 1); Console.WriteLine(myTest << 2); myTest <<= 2; Console.WriteLine(myTest); byte myGeorgi = 8; Console.WriteLine(myTest | myGeorgi); int squarePerimeter = 17; double squareSide = squarePerimeter / 4.0; double squareArea = squareSide * squareSide; Console.WriteLine(squareSide); // 4.25 Console.WriteLine(squareArea); // 18.0625 int a = 5; int b = 4; Console.WriteLine(a + b); // 9 Console.WriteLine(a + b++); // 9 Console.WriteLine(a + b); // 10 Console.WriteLine(a + (++b)); // 11 Console.WriteLine(a + b); // 11 Console.WriteLine(14 / a); // 2 Console.WriteLine(14 % a); // 4 a = 11; b = 2; // Arithmetic operators Console.WriteLine(a + b); Console.WriteLine(a - b); Console.WriteLine(a / b); Console.WriteLine(a * b); Console.WriteLine(a++); Console.WriteLine(a); Console.WriteLine(++a); Console.WriteLine(a % b); Console.WriteLine(--a); Console.WriteLine(a--); // For comparison Console.WriteLine(a > b); Console.WriteLine(a < b); Console.WriteLine(a >= b); Console.WriteLine(a <= b); Console.WriteLine(a == b); Console.WriteLine(a != b); // Logical bool x = true; bool y = false; Console.WriteLine(x && y); Console.WriteLine(x || y); Console.WriteLine(x ^ y); Console.WriteLine(!x); // for asignments a += 3; // a = a + 3; // Bitwise operators Console.WriteLine(1 << 1); Console.WriteLine(2 >> 1); Console.WriteLine(1 | 2); Console.WriteLine(1 & 2); Console.WriteLine(1 ^ 3);// 2 // int? a = 5; // int? b = 6 // a = null; // int? z = a ?? b; // long d = 3214321342134231443; // int i = checked((int)d); // System.OverflowException int one = 1; int zero = 0; // Console.WriteLine(one / zero); // DivideByZeroException double dMinusOne = -1.0; double dZero = 0.0; Console.WriteLine(dMinusOne / zero); // -Infinity Console.WriteLine(one / dZero); // Infinity Console.Clear(); Console.Write("Stoyan "); Console.Write("Cheresharov \n\r"); Console.WriteLine("My name is Desi. I am {0} years old. my favorite number is {1}", myDesiInt, 3); Console.WriteLine("| {0,10:######} |", 12); // Formatting Numbers // Standard Formatting Symbols C, D, E, F, N, P, X Console.WriteLine("{0:C2}", 123.456); //Output: 123,46 лв. Console.WriteLine("{0:D6}", -1234); //Output: -001234 Console.WriteLine("{0:E2}", 123); //Output: 1,23Е+002 Console.WriteLine("{0:F2}", -123.456); //Output: -123,46 Console.WriteLine("{0:N2}", 1234567.8); //Output: 1 234 567,80 Console.WriteLine("{0:P}", 0.456); //Output: 45,60 % Console.WriteLine("{0:X}", 254); //Output: FE // Custom Formatting Symbols 0000, ###, %, E0 Е+0 Е-0 Console.WriteLine("{0:0.00}", 1); //Output: 1,00 Console.WriteLine("{0:#.##}", 0.234); //Output: ,23 Console.WriteLine("{0:#####}", 12345.67); //Output: 12346 Console.WriteLine("{0:(0#) ### ## ##}", 29342525); //Output: (02) 934 25 25 Console.WriteLine("{0:%##}", 0.234);//Output: %23 // Standard Formatting Symbols for DateTime DateTime d = new DateTime(2018, 9, 14, 15, 30, 22); Console.WriteLine("{0:D}", d); // d D Console.WriteLine("{0:t}", d); // t T Console.WriteLine("{0:Y}", d); // y Y // Custom Formatting Symbols for DateTime d, dd, M, MM, yy, yyyy, hh, HH, m, mm, s, ss Console.WriteLine("{0:dd/MM/yyyy HH:mm:ss}", d); Console.WriteLine("{0:d.MM.yy г.}", d); // return; Console.Clear(); Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo("bg-Bg"); Console.WriteLine("| {0,10:C} |", 120000.4532); Console.Clear(); // Reading from the console and parsing Console.Write("Please enter your age: "); string inputVariable = Console.ReadLine(); // Parsing strings to numbers int age = int.Parse(inputVariable); double ageInDouble; double.TryParse(inputVariable, out ageInDouble); Console.WriteLine(Convert.ToInt16(inputVariable)); Console.WriteLine(age + 10); // Read a character from the input with Read //Console.Write("Please enter a character: "); //int nextChar = Console.Read(); //Console.WriteLine(nextChar); //Console.WriteLine((char)nextChar); // return; // ReadKey //Console.WriteLine("Please press ESC key to exit this endless loop"); //ConsoleKeyInfo cki; //do { // if (!Console.KeyAvailable) // { // Console.Clear(); // Console.WriteLine("Please hit Esc"); // } // cki = Console.ReadKey(true); // System.Threading.Thread.Sleep(50); //} while(cki.Key != ConsoleKey.Escape); Console.OutputEncoding = Encoding.UTF8; Console.ForegroundColor = ConsoleColor.Green; // Console.BackgroundColor = ConsoleColor.Blue; // To change the background color of the > console window as a whole, set the BackgroundColor property and call the Clear method. // Console.BackgroundColor = ConsoleColor.Blue; // Console.Clear(); Console.SetCursorPosition(5, 10); // left top Console.WriteLine("Това е кирилица: ☺"); Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo("en-GB"); // UK doesn't work // Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture; Console.WriteLine("Your balance is {0, 30:C2}", 1234567.8904534); //for (int charCode = 0; charCode < 1000; i++) //{ // Console.WriteLine((char)i); //} int secondNumber = 3; int firstNumber = 2; if (secondNumber > firstNumber) { // int biggerNumber = secondNumber; Console.WriteLine(secondNumber); } char ch = 'X'; if (ch == 'A' || ch == 'a') { Console.WriteLine("Vowel [ei]"); } else if (ch == 'E' || ch == 'e') { Console.WriteLine("Vowel [i:]"); } else if (ch == 'I' || ch == 'i') { Console.WriteLine("Vowel [ai]"); } else if (ch == 'O' || ch == 'o') { Console.WriteLine("Vowel [ou]"); } else if (ch == 'U' || ch == 'u') { Console.WriteLine("Vowel [ju:]"); } else { Console.WriteLine("Consonant"); } //if (булев израз) //{ // тяло на условната конструкция; //} //else //{ // тяло на else-конструкция; //} //switch (селектор) //{ // case целочислена - стойност - 1: конструкция; break; // case целочислена - стойност - 2: конструкция; break; // case целочислена - стойност - 3: конструкция; break; // case целочислена - стойност - 4: конструкция; break; // // … // default: конструкция; break; //} //while (условие) //{ // тяло на цикъла; //} // Initialize the counter int counter = 0; // Execute the loop body while the loop condition holds while (counter <= 9) { // Print the counter value Console.WriteLine("Number : " + counter); // Increment the counter counter++; } // n! = (n - 1)!*n Console.Write("Please, enter a number: "); int n = int.Parse(Console.ReadLine()); // "decimal" is the biggest type that can hold integer values decimal factorial = 1; // Perform an "infinite loop" while (true) { if (n <= 1) { break; } factorial *= n; n--; } Console.WriteLine("n! = " + factorial); int myDoTest = 0; do { Console.Write("Please enter a number betwen 0 and 5: "); myDoTest = int.Parse(Console.ReadLine()); } while (myDoTest > 5 || myDoTest < 0); //for (инициализация; условие; обновяване) //{ // тяло на цикъла; //} for (int j = 0; j <= 10; j++) { Console.Write(j + " "); } int t = 0; while (t < 10) { // i++; // break; if (t % 2 == 0) { t++; continue; } Console.WriteLine("t = " + t); t++; } int[] numbers = { 2, 3, 5, 7, 11, 13, 17, 19 }; foreach (int k in numbers) { Console.Write(" " + k); } Console.WriteLine(); String[] towns = { "Sofia", "Plovdiv", "Varna", "Bourgas" }; foreach (String town in towns) { Console.Write(" " + town); } int special = 34; Console.WriteLine($"This is my variable {special}"); Console.BackgroundColor = ConsoleColor.DarkBlue; Console.Clear(); Console.ForegroundColor = ConsoleColor.Yellow; string[] students = new string[100]; students[0] = "Konstantin"; students[1] = "Angel"; Console.WriteLine(students[0]); int[] myArray = { 1, 2, 3, 4, 5, 6 }; int[] myArray2 = new int[3] { 23, 45, 67 }; string[] daysOfWeek = { "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" }; int[] array = new int[] { 1, 2, 3, 4, 5 }; Console.Write("Output: "); for (int index = 0; index < array.Length; index++) { // Doubling the number array[index] = 2 * array[index]; // Print the number Console.Write(array[index] + " "); } // Output: 2 4 6 8 10 //foreach (var item in collection) //{ // // Process the value here //} int[,] matrix = { {1, 2, 3, 4}, // row 0 values {5, 6, 7, 8}, // row 1 values }; // The matrix size is 2 x 4 (2 rows, 4 cols) Console.WriteLine(); Console.WriteLine(matrix[0,3]); // 4 Console.WriteLine(matrix.GetLength(0)); Console.WriteLine(matrix.GetLength(1)); int[][] myJaggedArray = { new int[] {5, 7, 2}, new int[] {10, 20, 40}, new int[] {3, 25}, new int[] { 1,2,3,4,5,6,78,9} }; int[][,] jaggedOfMulti = new int[2][,]; // another way to declare jagged array int[][] jaggedArray; jaggedArray = new int[2][]; jaggedArray[0] = new int[5]; jaggedArray[1] = new int[3]; // String number = "100"; // int fromBase = 16; // int toBase = 10; // String result1 = Convert.ToString(Convert.ToInt32(number, fromBase), toBase); // result == "256" // Console.WriteLine(result1); /* // Convert to binary system Console.Write("Please, enter a number to convert to binary: "); // with 340282366920938000000000000000000000000 // System.OverflowException: Value was either too large or too small for an Int32. int number2Convert = int.Parse(Console.ReadLine()); int[] binaryNumber = new int[128]; // the default value is 0 int digitCounter = 127; while (number2Convert > 0 && digitCounter > 0) { binaryNumber[digitCounter] = number2Convert % 2; digitCounter--; number2Convert /= 2; Console.WriteLine(number2Convert); } foreach (var digit in binaryNumber) { Console.Write(digit); } Console.WriteLine(); Console.WriteLine(Math.Pow(2, 128)); // 3.40282366920938E+38 // Console.WriteLine("{0,10:N}", Math.Pow(2, 128)); // 340,282,366,920,938,000,000,000,000,000,000,000,000.00 // Console.WriteLine("{0,10:D}", Math.Pow(2, 128)); // Exception Console.WriteLine("{0,10:F0}", Math.Pow(2, 128)); // 340282366920938000000000000000000000000 // https://stackoverflow.com/questions/2954962/convert-integer-to-binary-in-c-sharp int value = 8; string binary = Convert.ToString(value, 2); // Convert from any classic base to any base in C# String number = "100"; int fromBase = 16; int toBase = 10; String result = Convert.ToString(Convert.ToInt32(number, fromBase), toBase); // result == "256" // Supported bases are 2, 8, 10 and 16 */ // Convert from decimal to binary system //34 - > 100010 = 1 * 2 ^ 5 + 0 + 0 + 0 + 1 * 2 ^ 1 + 0 = 32 + 2 = 34 //34 : 2 = 17 0 //17 : 2 = 8 1 //8 : 2 = 4 0 //4 : 2 = 2 0 //2 : 2 = 1 0 // 1 //100010 //100010 // 8| 4 | 2 | 1 // e.g. 12 is 8 + 4 then we put 1 in positions of 8 and 4 -> 1100 // Convert form base 16 to base 2 //0010 | 1010 | 1010 | 1010 | 1111 | 1110 | 0001 | 1111 | 1111 //2AAAFD1FF // Method calls string[] studentsTemp = new string[2]; InputNames(studentsTemp); InputNames(studentsTemp, 5); InputNames(studentsTemp, 3, 2, 3, 4, 5, 6, 2, 3, 6, 6); InputNames(n: 6, names: studentsTemp); // Recursion int factorial2 = 5; Console.WriteLine("!{0} = {1}", factorial2, Factorial(factorial2)); // Standard Math functions Console.WriteLine(Math.Cos(23)); // every string can be used as array string stoyanName = "Stoyan"; Console.WriteLine(stoyanName[0]); // S // string functions - tyme the name of the variable and . Console.WriteLine(stoyanName.IndexOf('t')); // etc. } // Method declaration and definition, default parameters, variable number of parameters static void InputNames(string[] names, int n = 4, params int[] myExtraParams) { for (var i = 0; i < names.Length; i++) { Console.Write("Please enter element number {0} :", i); names[i] = Console.ReadLine() + " Default Mark = " + n + " Final Mark" + ((myExtraParams.Length > 0) ? myExtraParams[i].ToString() : "0"); // Console.WriteLine(names[i]); } } // Recursion // !n = !(n-1) * n static int Factorial(int n) { if (n == 0) return 1; return Factorial(n - 1) * n; } } }