static void Main(string[] args)
{
var numbers = new List <int>()
{
1, 2, 3, 4
}; //deklaracja listy z wartościami
numbers.Add(1); //dodanie elementu do listy
numbers.AddRange(new int[3] {
5, 6, 7
}); //dodanie tablicy do listy
foreach (int num in numbers)
{
Console.WriteLine(num);
}
Console.WriteLine();
//IndexOf()
var pos = numbers.IndexOf(1); //1. wystąpienie wartości
Console.WriteLine(pos);
var pos2 = numbers.LastIndexOf(1); //ostatnie wystąpienie wartości
Console.WriteLine(pos2);
Console.WriteLine();
//Count - długość listy
Console.WriteLine("Count: " + numbers.Count);
//Remove //usunięcie pierwszego wystąpienia danej wartości
//numbers.Remove(1);
/*foreach (int num in numbers) // NIE WOLNO UŻYWAC FOREACH DO USUWANIA EL. Z LISTY
* {
* if(num ==1)
* numbers.Remove(num);
*
* }*/
Console.WriteLine();
for (var i = 0; i < numbers.Count; i++)
{
if (numbers[i] == 1)
{
numbers.Remove(numbers[i]);
}
}
foreach (int num in numbers)
{
Console.WriteLine(num);
}
//Clear - usuwa wszystkie elementy z listy
numbers.Clear();
Console.WriteLine("Count: " + numbers.Count);
}
static void Main(string[] args)
{
var numbers = new List <int>()
{
1, 2, 3, 4
};
// Add() --> it adds an object to a list
numbers.Add(1);
// AddRange() --> add another list or array of lists
numbers.AddRange(new int[3] {
5, 6, 7
});
foreach (var n in numbers)
{
Console.WriteLine(n);
}
/*
* IndexOf()
* - returns the index of a given object or '-1' if object doesn't exist
* - it searches from the beginning of the List
* - LastIndexOf searches from the end of the List
*/
Console.WriteLine("Index of 1: " + numbers.IndexOf(1));
Console.WriteLine("Last Index of 1: " + numbers.LastIndexOf(1));
// Count() --> returns the number of objects in the list
Console.WriteLine("Count: " + numbers.Count());
/*
* Remove()
* - cannot modify a collection from within a 'foreach' group
*/
for (int i = 0; i < numbers.Count; i++)
{
if (numbers[i] == 1)
{
numbers.Remove(numbers[i]);
}
}
foreach (var number in numbers)
{
Console.WriteLine(number);
}
// we removed both '1s' from the list
// Clear() --> removes all items from the List
numbers.Clear();
Console.WriteLine("Count of numbers: " + numbers.Count());
// Exercises
var exercises = new Exercises();
//exercises.Number1();
//exercises.Number2();
//exercises.Number3();
//exercises.Number4();
exercises.Number5();
}
static void Main(string[] args)
{
List <int> listOfNumbers = new List <int>()
{
1, 2, 3, 4
};
// Add and AddRange
listOfNumbers.Add(5);
listOfNumbers.AddRange(new int[] { 6, 7, 8 });
foreach (int number in listOfNumbers)
{
Console.Write(number + " ");
}
Console.WriteLine();
// IndexOf and LastIndexOf
int n = listOfNumbers.IndexOf(1);
Console.WriteLine("Index of 1: " + n);
int n2 = listOfNumbers.LastIndexOf(3);
Console.WriteLine("Last index of 3: " + n2);
// Count
Console.WriteLine("Count of elements: " + listOfNumbers.Count);
// Remove
listOfNumbers.Remove(1);
foreach (int num in listOfNumbers)
{
Console.Write(num + " ");
}
Console.WriteLine();
listOfNumbers.RemoveAt(0);
foreach (int num in listOfNumbers)
{
Console.Write(num + " ");
}
Console.WriteLine();
for (int i = 0; i < listOfNumbers.Count; i++)
{
if (listOfNumbers[i] == 6)
{
listOfNumbers.RemoveAt(i);
}
}
foreach (int num in listOfNumbers)
{
Console.Write(num + " ");
}
Console.WriteLine();
listOfNumbers.Clear();
foreach (int num in listOfNumbers)
{
Console.Write(num + " ");
}
Console.WriteLine(listOfNumbers.Count);
}
static void Main(string[] args)
{
// Lists are dynamic, whereas Arrays are static
// Lists are a generic type
// Example List
var numbers = new List <int>()
{
1, 2, 3, 4
};
numbers.Add(1);
numbers.AddRange(new int[3] {
5, 6, 7
});
foreach (var number in numbers)
{
Console.WriteLine(number);
}
// IndexOf()
Console.WriteLine("Index of 1: " + numbers.IndexOf(1));
// LastIndexOf()
Console.WriteLine("Last Index of 1: " + numbers.LastIndexOf(1));
// Count
Console.WriteLine("Count: " + numbers.Count);
// Remove
// foreach throws error, so use regular for loop
//foreach (var number in numbers)
//{
// if (number == 1)
// numbers.Remove(number);
//}
for (var i = 0; i < numbers.Count; i++)
{
if (numbers[i] == 1)
{
numbers.Remove(numbers[i]);
}
}
foreach (var number in numbers)
{
Console.WriteLine(number);
}
// Clear()
numbers.Clear();
Console.WriteLine("Count: " + numbers.Count);
Console.WriteLine();
// Useful List methods
// Add()
// AddRange()
// Remove()
// RemoveAll()
// IndexOf()
// Contains()
// Count
}