Question

我想使用ArrayList对nums []进行排序，但它只能传递17/83个案例。我不知道我做错了什么。

public class Solution {
   public void sortColors(int[] nums) {
       List<Integer> list = new ArrayList<Integer>();
       List<Integer> redList = new ArrayList<Integer>();
       List<Integer> whiteList = new ArrayList<Integer>();
       List<Integer> blueList = new ArrayList<Integer>();

       if(nums==null||nums.length==0)
          return ;

       for(int number:nums){
           switch (number){
               case 0:
                  redList.add(number);
                  break;
               case 1:
                  whiteList.add(number);
                  break;
               case 2:
                  blueList.add(number);
                  break;
               default:
                  break;
           }
       }
       list.addAll(redList);
       list.addAll(whiteList);
       list.addAll(blueList);
   }
}

它占用了大量的额外空间，但我认为它可以比插入排序更快。

Answer 1

检查API到期Collections.sort

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class Main {

public static void main(String[] args) {
    //Must be Integer class
    Integer[] nums = { 1, 2, 3, 0, 1, 2, 3, 1, 4, 4, 4, 0, 0, 1, 2, 1, 0,
            0, 4 };

    List<Integer> list = Arrays.asList(nums);
    // Before sort
    System.out.println("Before sort :" + list.toString());

    // Sort 'list' items
    Collections.sort(list);
    // After sort
    System.out.println("After sort :" + list.toString());
}

输出：

Before sort :[1, 2, 3, 0, 1, 2, 3, 1, 4, 4, 4, 0, 0, 1, 2, 1, 0, 0, 4]
After sort :[0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 4, 4]

LeetCode排序颜色java

1 个答案: