MinMax.java

package com.sky;

import java.io.*;

public class MinMax {

    public static void main(String[] args) {
        int min = 0;
        int max = 0;

        long before = System.currentTimeMillis();

        File file = new File("data"); // integers inside are ranged from -5000000 to 5000000
        BufferedReader reader = null;

        try {
            reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
            String line = reader.readLine();

            while (line != null) {
                int value = Integer.parseInt(line);

                if (value > max) max = value;
                if (value < min) min = value;

                line = reader.readLine();
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) reader.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }

        long after = System.currentTimeMillis();

        System.out.println("run took " + (after - before) / 1000 + " s");
        System.out.format("min: %d\n", min);
        System.out.format("max: %d", max);
    }
}