Lectures

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In this Kotlin lecture, we’ll figure out why we need real numbers, how Double and Float differ, why a literal with a decimal point most often becomes Double, why Float requires the f suffix, how division of Int by Int works, and what scientific notation like 1e-3 means. At the end, we’ll cover common mistakes that make the fractional part “disappear”.

In this Kotlin lecture, you will understand why the expression 0.1 + 0.2 is not required to produce exactly 0.3, why comparing Double with == is a trap, how epsilon comparison works via abs, and also what the special values NaN and Infinity are, how to check them with isNaN and isInfinite, and how to protect calculations from being “infected” by non-numeric results.

In this Kotlin lecture, you will figure out how the rounding functions from the kotlin.math package work — floor, ceil, round — why they behave differently for negative numbers, what “round half to even” (banker’s rounding) is, and how mathematical rounding differs from type conversion via toInt(). At the end: practical techniques, a comparison table, and common mistakes.

In this Kotlin lecture, you will learn how to generate pseudorandom values with kotlin.random.Random: get random Int and Double, set correct bounds in Random.nextInt ( from inclusive, until exclusive), scale nextDouble to the desired range, and round the result for “human-friendly” output. At the end — a mini-project LuckyCafe and a list of typical mistakes.

In this Kotlin lecture, we’ll break down why numeric type conversions are almost always explicit, how the methods toInt(), toDouble(), toFloat() work, why conversions Double → Int can be dangerous, and also how the Char type is designed: the code property, conversion via toChar(), working with digits '0'.. '9', and a mini-scenario for generating a coupon.

In this lecture, you will learn how the IT product development process is structured: what roles exist on the team, how they interact, what Product Owners, UX Designers, DevOps, and developers do, and you will also get acquainted with the history of how approaches to building modern digital services have evolved.