一維最接近點對的分治解法

import java.util.Arrays;
import java.util.Scanner;

/*
 * 用分治法輸出一個一維數組中的n個不同實數間距離最小的兩個實數。輸入：實數數組X, 實數個數n, 輸出: 距離最小的兩個實數.
 * */
public class Divided {

	private static float[] X;
	private static int a = 0;
	private static int b = 0;
	private static float min = Float.MAX_VALUE;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		X = new float[n];
		for (int i = 0; i < n; i++) {
			X[i] = sc.nextFloat();
		}
		Arrays.sort(X);
		fun(0, n - 1);
		System.out.println(X[a]);
		System.out.println(X[b]);
	}

	private static void fun(int low, int high) {
		if (low == high) {
			return;
		}
		if (low + 1 == high) {
			if (min > Math.abs(X[high] - X[low])) {
				min = Math.abs(X[high] - X[low]);
				a = low;
				b = high;
			}
		} else {
			int mid = (low + high) / 2;
			fun(low, mid);
			fun(mid + 1, high);
			if (min > Math.abs(X[mid] - X[mid + 1])) {
				min = Math.abs(X[mid] - X[mid + 1]);
				a = mid;
				b = mid + 1;
			}
		}
	}
}