List of lectures for the course Go, 14 quest level on JavaRush

string as immutable bytes
Go SELF
14 level,0 lecture
We break down the string model in Go: why string is a sequence of bytes, why strings are immutable, what expressions len ( s ), s [ i ], and s [ a : b ] actually return, how to avoid panic: index out of range, and how to “modify” a string correctly—by creating a new one. In practice, we will write an ASCII function titleASCII() and learn to diagnose strings by printing them byte by byte.
Open
rune and iterating over a string with range: length in bytes vs runes
Go SELF
14 level,1 lecture
In this lecture, we will break down why for strings in Go len(s) counts UTF‑8 bytes rather than “letters”, what the rune type is (an alias for int32), and how a for loop with range decodes a string into runes, returning the byte index and the character. In practice, we will learn how to count “length in characters”, safely take a prefix of the first N runes (without [] rune), and avoid common mistakes like s[0] on UTF‑8 strings and slicing a string at invalid boundaries.
Open
Conversions of []byte and []rune and when they are appropriate
Go SELF
14 level,2 lecture
We break down how strings ( string) are implemented in Go and why they are immutable; how the representations []byte (UTF-8 bytes) and []rune (Unicode code points) differ; what exactly indexing s [ i ] returns; why conversions []byte(s)/ []rune(s) copy the data; and how to choose the right approach for “technical” replacements (for example, "\t", "\n") and for “character-by-character” operations (Cyrillic/Unicode).
Open
strings and bytes: Trim/Split/Join and Builder/Buffer
Go SELF
14 level,3 lecture
We break down practical string and byte operations in Go: how to normalize input using strings/ bytes, apply TrimSpace, Split, and Join, and how to efficiently build a result without concatenation via +—using strings.Builder and bytes.Buffer. Separately, we will reinforce the difference between calling a package function (for example, fmt. Println) and calling a method on a value (for example, b. WriteString).
Open
Debugging strings: %q and controlling “dirty” input
Go SELF
14 level,4 lecture
Let’s break down how to diagnose “dirty” input in Go: why fmt.Println() can hide characters, how to print strings with an “X-ray” via fmt.Printf() using the %q format, how to view exact bytes via []byte, iterate over Unicode as runes via range, and normalize input using strings.TrimSpace() after reading with ReadString('\n'). At the end: common mistakes and a quick algorithm for finding invisible "\r"/ "\n"/ "\t".
Open