Bounded Counter Class

/*
 * Problem : Run the commands.
 * Input   : Command lines.
 * Output  : One line per answer.
 * Approach: Counter class
 * Time    : O(n)
 * Space   : O(1)
 * Java    : 8 or newer.
 */
import java.util.Scanner;

public class Main {
        // Step 1: The class owns the limits. Nobody outside can put the value out of range.
        static class Counter {
            private final long low;
            private final long high;
            private long value;

            Counter(long low, long high, long start) {
                this.low = low;
                this.high = high;
                this.value = start;
            }

            // Step 2: Each change is cut back to the allowed range.
            void inc(long k) {
                value = Math.min(high, value + k);
            }

            void dec(long k) {
                value = Math.max(low, value - k);
            }

            void reset() {
                value = low;
            }

            long get() {
                return value;
            }
        }

    // This method solves the task. It receives the input and returns the answer.
    static String[] solve(String[] lines) {
        String[] head = lines[0].split(" ");
        Counter counter = new Counter(Long.parseLong(head[0]), Long.parseLong(head[1]), Long.parseLong(head[2]));
        java.util.List<String> out = new java.util.ArrayList<String>();
        for (int i = 1; i < lines.length; i++) {
            String[] part = lines[i].split(" ");
            if (part[0].equals("inc")) {
                counter.inc(Long.parseLong(part[1]));
            } else if (part[0].equals("dec")) {
                counter.dec(Long.parseLong(part[1]));
            } else if (part[0].equals("reset")) {
                counter.reset();
            } else {
                out.add(String.valueOf(counter.get()));
            }
        }
        return out.toArray(new String[0]);
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        java.util.List<String> all = new java.util.ArrayList<>();
        while (scanner.hasNextLine()) {
            String line = scanner.nextLine().trim();
            if (!line.isEmpty()) {
                all.add(line);
            }
        }
        String[] lines = all.toArray(new String[0]);
        System.out.println(String.join("\n", solve(lines)));
    }
}