03-AddingRemovingElements.js

// @ts-check

function printArray(myArray) {
  for (var i = 0; i < myArray.length; i++) {
    console.log(myArray[i]);
  }
}

var numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];

// add a new element to the numbers array
numbers[numbers.length] = 10;

numbers.push(11);

numbers.push(12, 13);

printArray(numbers);

// insert first position manually
for (var i = numbers.length; i >= 0; i--) {
  numbers[i] = numbers[i - 1];
}

numbers[0] = -1;

printArray(numbers);

// using method unshift
numbers.unshift(-2);

printArray(numbers);

numbers.unshift(-4, -3);

printArray(numbers);

// **** Removing elements

numbers.pop();

// remove first position manually
/* for (var i=0; i<numbers.length; i++){
    numbers[i] = numbers[i+1];
}*/

printArray(numbers);

console.log(numbers.length);

// using method shift
numbers.shift();

printArray(numbers);
console.log(numbers.length);

//* *** Removing and Adding elements from the middle of the array or specific position
// splice method - parameter (index, howManyPositionsToBeRemoved, item1...itemX)
numbers.splice(5, 3);

console.log('----');

printArray(numbers);

numbers.splice(5, 0, 2, 3, 4);

console.log('----');

printArray(numbers);

console.log('----');

numbers.splice(5, 3, 2, 3, 4);

printArray(numbers);