题解 | 二叉排序树

import java.util.*;

import java.io.*;

public class Main {

    public static void main(String [] args) {
        Scanner in = new Scanner(System.in) ;
        while (in.hasNext()) {
            int n = in.nextInt();
            int[][] array = new int[n][4];
            for (int i = 0; i < n; i++)
                array[i] = new int[] {-1, -1, -1, -1};
            for (int i = 0; i < n; i++) {
                array[i][0] = in.nextInt();
                for (int j = 0; j != i ;) {
                    int u = (array[j][0] > array[i][0]) ? 2 : 3;
                    if (array[j][u] == -1) {
                        array[j][u] = i;
                        array[i][1] = array[j][0];
                        break;
                    }
                    j = array[j][u];
                }
                System.out.println(array[i][1]);
            }
        }
    }
}