03. Take/Skip Rope

package MoreExercise;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class TakeSkipRope {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);


        String textChain = scanner.nextLine();
        List<Integer> numbers = new ArrayList<>();
        List<Character> nonNumbers = new ArrayList<>();

        // Step 1: Extract digits and non-digits
        for (char c : textChain.toCharArray()) {
            if (Character.isDigit(c)) {
                numbers.add(Character.getNumericValue(c));
            } else {
                nonNumbers.add(c);
            }
        }

        // Step 2: Separate take and skip lists
        List<Integer> take = new ArrayList<>();
        List<Integer> skip = new ArrayList<>();
        for (int i = 0; i < numbers.size(); i++) {
            if (i % 2 == 0) {
                take.add(numbers.get(i));
            } else {
                skip.add(numbers.get(i));
            }
        }

        // Step 3: Construct the result string
        StringBuilder result = new StringBuilder();
        int nonNumIndex = 0;
        for (int i = 0; i < take.size(); i++) {
            int takeCount = take.get(i);
            int skipCount = skip.get(i);
            for (int j = 0; j < takeCount && nonNumIndex < nonNumbers.size(); j++) {
                result.append(nonNumbers.get(nonNumIndex++));
            }
            nonNumIndex += skipCount;
        }

        System.out.println(result.toString());
    }
}