a function which takes a list of strings and returns each line prepended by the correct number @der amateur

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a function which takes a list of strings and returns each line prepended by the correct number

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Write a function which takes a list of strings and returns e

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2021-08-22 16:16:20 By

Write a function which takes a list of strings and returns each line prepended by the correct number.

The numbering starts at 1. The format is n: string. Notice the colon and space in between.

Examples:

number(Arrays.asList()) # => []
number(Arrays.asList("a", "b", "c")) // => ["1: a", "2: b", "3: c"]

my solution according to: https://github.com/RomanBulinski/Testing1-2-3.git

import java.util.List;

import java.util.concurrent.atomic.AtomicInteger;

import java.util.stream.Collectors;

import static java.util.stream.Collectors.toList;

public class Main {

public static List<String> number(List<String> lines) {

AtomicInteger i = new AtomicInteger(1);

return lines.stream().map(e -> i.getAndIncrement() + ": " + e).collect(Collectors.toList());

}

best practice:

import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

class LineNumbering {
    static List<String> number(List<String> lines) {
    if (lines.size() == 0) return lines;
    return IntStream.range(0, lines.size())
            .mapToObj(n -> String.format("%d: %s", n+1, lines.get(n)))
            .collect(Collectors.toList());
    }
}

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