Swift Language Guide 2 - Basic Operators

Question 1

Jake druhy operatoru jsou ve Swiftu?

Answer 1

Unarni, binarni a ternarni.

Question 2

Co dela prirazovaci operator?

Answer 2

Inicializuje nebo updatuje konstantu nebo promennou.

let a = 10

Question 3

Jake jsou aritmeticke operatory?

Answer 3

+, -, *, /.

Question 4

Co dela zbytkovy operator?

Answer 4

Vraci zbytek po deleni.

9 % 4 // equals 1

Question 5

Co dela inkrementacni a dekrementacni operatory?

Answer 5

Zvyseje o 1, resp. snizuje o 1.

++a

–b

Question 6

Jake jsou unarni operatory?

Answer 6

Minusovy a plusovy operator

-a

+b

Question 7

Co je to slozeny prirazovaci operator?

Answer 7

Kombinuje prirazovaci operator s jinym operatorem.

a += 10

Question 8

Jake jsou porovnavaci operatory?

Answer 8

==, !=, >, <, >=, <=.

Question 9

Jakou formu ma ternarni podminkovy operator a co dela?

Answer 9

Ma formu otazka ? odpoved1 : odpoved2. Pokud je otazka pravdiva provede se odpvoed1 jinak odpoved2.

let contentHeight = 40

let hasHeader = true

let rowHeight = contentHeight + (hasHeader ? 50 : 20)

// rowHeight is equal to 90

Question 10

Co je to nil slucovaci operator a jakou ma formu?

Answer 10

Ma formu (a ?? b). Pokud optional a neni nil, potom se unwrapuje a, pokud je nil vraci hodnotu b.

let defaultColorName = “red”

var userDefinedColorName: String? // defaults to nil

var colorNameToUse = userDefinedColorName ?? defaultColorName

// userDefinedColorName is nil, so colorNameToUse is set to the default of “red”

Question 11

Jake jsou rozsahove operatory a jakou maji syntaxi.

Answer 11

Uzavreny rozsahovy operator (a..b).

Z poloviny otevreny rozsahovy operator (a..

Question 12

Jake jsou logicke operatory?

Answer 12

NOT (!a), AND (a && b), OR (a || b).