JuniorTheoryCommon

What does the program print?

package main

import (
    "fmt"
    "unicode/utf8"
)

func main() {
    s := "héllo"
    fmt.Println(len(s), utf8.RuneCountInString(s))
}

6 5

Expecting 5 5: len counts bytes, not characters, and é takes two bytes in UTF-8, so the string is 6 bytes long.
Expecting two bytes per character for every letter: Go strings hold UTF-8, where each Latin letter takes one byte and é takes two.