Google Code Jam 2011 A

A.java

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;

public class A {

	public static void main(String[] args) throws IOException {
		String inputFileName = "input-file.in";

		File inputFile = new File(inputFileName);
		FileInputStream fis = new FileInputStream(inputFile);
		InputStreamReader isr = new InputStreamReader(fis);
		BufferedReader br = new BufferedReader(isr);
		
		BufferedWriter out = new BufferedWriter(new FileWriter("resource/a.out"));

		try {

			String msg;
			int q = Integer.parseInt(br.readLine());
			int count = 1;
			
			while ((msg = br.readLine()) != null) {
				String[] split = msg.split(" ");

				CardShuffle cs = new CardShuffle(Integer.parseInt(split[0]),
						Integer.parseInt(split[1]), Integer.parseInt(split[2]));

				for (int i = 0; i < cs.c; i++) {
					msg = br.readLine();
					String[] split2 = msg.split(" ");
					cs.cut(Integer.parseInt(split2[0]),
							Integer.parseInt(split2[1]));
				}


				out.write("Case #" + (count++) + ": " + (cs.getCard()));
				out.newLine();
				
			}

		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			br.close();
			out.close();
		}
	}
}

CardShuffle.java

import java.util.ArrayList;

public class CardShuffle {
	ArrayList<Integer> card;
	int m;
	int c;
	int w;

	public CardShuffle(int m, int c, int w) {
		this.card = new ArrayList<Integer>(m);
		for (int i = 1; i <= m; i++) { // カード初期化
			card.add(i);
		}
		this.m = m;
		this.c = c;
		this.w = w;
	}

	public int getCard() {
		return card.get(w - 1);
	}

	public void cut(int ai, int bi) {
		ArrayList<Integer> al = new ArrayList<Integer>();

		for (int i = ai; i <= (ai + bi - 1); i++) {
			al.add(card.get(i - 1));
		}
		
		if (card.size() != 1) {
			card.subList(ai-1, (ai + bi - 1)).clear();
		}

		al.addAll(card);

		card = al;
	}
}