LESSON 373 OF 414 · PROJECTS: COMMAND-LINE TOOLS

CLI Tool: cat v1 — Print Lines in Scala

Practice

Build a tiny version of the Unix cat command. Given a list of lines, return them joined by newline characters (\n) so they print one per line.

Lines can be blank, and the list can be empty (the result is then an empty string).

Function signature:

def cat(lines: List[String]): String

Example:

Input: lines = ["hello", "world", "foo"]

Output: "hello\nworld\nfoo"

When printed:
hello
world
foo

Think of the output as one big String where each input line is separated from the next by a newline character. Scala's List has a method that glues all of its elements together with a chosen separator.

Call lines.mkString("\n") — the separator goes between every pair of lines.

The full solution is a one-liner:

class Solution {
    def cat(lines: List[String]): String = {
        return lines.mkString("\n")
    }
}

STEP 1 OF 1

Guided

Ctrl + Enter to check

CLI Tool: cat v1 — Print Lines in Scala

Cat V1 in Scala