import java.io.*;
import java.util.regex.*;
import java.lang.Math;

public class DataMunging {

    public static void main(String[] args) throws IOException {
        BufferedReader in = null;
        String target = null;
        int minDay = 0;
        int minSpread = 100;

        try {
            in = new BufferedReader(new FileReader ("weather.dat"));
            Pattern p = Pattern.compile("^\\s+(\\d+)\\s+(\\d+)\\s+(\\d+)");
            System.out.println("Pattern: " + p.pattern());

            while (true) {
                target = in.readLine();

                if (target == null)
                        break;

                Matcher m = p.matcher(target);
                if (m.find()) {
                    int ID = Integer.parseInt(m.group(1));
                    int maxT = Integer.parseInt(m.group(2));
                    int minT = Integer.parseInt(m.group(3));

                    int spread = Math.abs(maxT - minT);

                    if (spread < minSpread) {
                        minSpread = spread;
                        minDay = ID;
                    }
                }
            }

        } finally {
            if (in != null) {
                in.close();
            }
        }

        System.out.println("Done parsing file!");
        System.out.println("Smallest spread day is #" + minDay + ", spread is " + minSpread + "°");
    }
}