ソート課題

Main.java

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

public class Main {
    
    public static void main(String[] args) {
        long base = System.currentTimeMillis();
        int[] array = new int[10000000];
        int count = 0;
        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
            String line;
            for (count = 0; (line = br.readLine()) != null; count++) {
                array[count] = Integer.parseInt(line);
            }
        }catch(IOException ex){
            
        }
        sort(array, 0 , count-1);
        for(int i = 0; i < array.length; i++) System.out.println(array[i]);
        System.err.println("ソート完了 : " + (base - System.currentTimeMillis()) + "ms");
    }
    

    public static void sort(int[] a, int begin, int end) {
        if (end <= begin) return;

        int i = begin;
        int less = begin;
        int greater = end;

        while (i <= greater){
            if (a[i] < a[less]) {
                int tmp = a[i];
                a[i] = a[less];
                a[less] = tmp;
                i++;
                less++;
            } else if (a[less] < a[i]){
                int tmp = a[i];
                a[i] = a[greater];
                a[greater] = tmp;
                greater--;
            } else {
                i++;
            }
        }

        sort(a, begin, less - 1);
        sort(a, greater + 1, end);
    }
}