TypeScript Online Test

Your company is analyzing malware which targets numerical record files.

The malware uses a sliding window over the array of numbers in a file, and tries to match the following pattern:

T, -, -, X, -, -, -, T

Where the position ‘X' is compared to each position 'T'. The window is moved so 'X’ passes through all the values.

The malware has the following rules:

• If any of the ‘T' positions in the pattern are bigger or equal to 'X’ the malware replaces 'X' with 0.
• If the 'X' position in the pattern is near the left or right border and is missing a 'T' position neighbor, only the other side is considered.
• The malware finds all the positions first and only then sets them to 0.

For example, if the values in a record file are the following:

[1, 2, 0, 5, 0, 2, 4, 3, 3, 3]

The expected values after the malware runs are:

[1, 0, 0, 5, 0, 0, 0, 3, 3, 0]

In this example, number 4 was set to 0 because 5 is the bigger number.

Implement the simulate function so that the malware behavior is replicated for further study.

The Circle class is used in a prototype for a game engine. Finish the class so that:

• It inherits from the GameObject class
• It has one more public field, radius
• It has only one constructor, that sets the radius, and sets the x and y fields using the GameObject class

For example, executing the following code:

let circle = new Circle(10, 50, 8);
console.log(circle.x, circle.y, circle.radius);

should print "10 50 8".

Extend the Permission enum so that it has the following fields:

• Read, which should have a value of 1
• Write, which should have a value of 2
• Execute, which should have a value of 4

Extend the getPermissionList function so that it accepts a combination of several Permission enums and returns an array of strings which are the names of the Permissions.

For example, executing:

getPermissionList(Permission.Read | Permission.Write);

should return [ 'Read', 'Write' ] in any order.

Your company assigns each customer a membership ID, and you are implementing a check digit for those IDs.

The check digit should be calculated by adding up all digits in each membership ID. If the result of the sum is a number with more than a single digit, another iteration is required, and the digits of the result should also be added together. This process should repeat until a single-digit number is calculated.

For example, for the membership ID "55555" the sum of all digits is 25. Because this is not a single-digit number, 2 and 5 would be added, and the result, 7, would be the check digit.

Consider the following code:

class Positionable {
  locationX: number = 0;
  locationY: number = 0;
  moveTo(toX: number, toY: number) {
    this.locationX = toX;
    this.locationY = toY;
  }
}

class Rotatable {
  orientation: number = 0;
  rotate(orientation: number) {
    this.orientation += orientation;
  }
}

class MovingObject {
  locationX: number = 0;
  locationY: number = 0;
  orientation: number = 0;
  printPosition(){
    console.log(this.locationX, this.locationY);
  }
}

function applyMixins(derivedCtor: any, baseCtors: any[]) {
  baseCtors.forEach(baseCtor => {
    Object.getOwnPropertyNames(baseCtor.prototype).forEach(name => {
      derivedCtor.prototype[name] = baseCtor.prototype[name];
    });
  });
}

applyMixins(MovingObject, [Positionable, Rotatable]);
let mover = new MovingObject();

Select the statements that are correct.

The following code initializes strings as three different types and attempts to make them uppercase. Which statements about the behavior of the typescript compiler are correct?

let stringType: string = "string type";
stringType.toUpperCase();

let anyType: any = "any type";
anyType.toUpper();
anyType.toUpperCase();

let objectType: Object = "object type";
objectType.toUpperCase();

The following code initializes three types representing the colors: red, green and blue.

type ColorType = [string, number, number, number];
let red: ColorType = ['Red', 1, 0, 0];
let green: [string, number, number, number] = ['Green', 0, 1, 0];
let blue = ['Blue', 0, 0, 1];

Select the statements that are correct.