19.2.13 [LeetCode 75] Sort Colors
Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white and blue.
Here, we will use the integers 0, 1, and 2 to represent the color red, white, and blue respectively.
Note: You are not suppose to use the library's sort function for this problem.
Example:
Input: [2,0,2,1,1,0]
Output: [0,0,1,1,2,2]
Follow up:
- A rather straight forward solution is a two-pass algorithm using counting sort.
First, iterate the array counting number of 0's, 1's, and 2's, then overwrite array with total number of 0's, then 1's and followed by 2's. - Could you come up with a one-pass algorithm using only constant space?
题意
给只包含0,1,2的数组排序
题解
1 class Solution { 2 public: 3 void sortColors(vector<int>& nums) { 4 int zero = -1, one = -1, n = nums.size(), i = 0; 5 while (i < n) { 6 if (nums[i] == 0) { 7 ++zero,++one; 8 nums[zero] = 0; 9 if(one>zero)nums[one] = 1; 10 if (one < i)nums[i] = 2; 11 } 12 else if (nums[i] == 1) { 13 ++one; 14 swap(nums[one], nums[i]); 15 } 16 i++; 17 } 18 } 19 };
感觉数算往年题看见过类似的题型,还是挺有趣的
虽然我还是WA了好几遍过的
狂赌之渊啥时候出熟肉啊,为啥生肉播放还不流畅x
注定失败的战争,也要拼尽全力去打赢它;
就算输,也要输得足够漂亮。