topic
Given an array of n elements containing red, white, and blue, sort them in place so that the elements of the same color are adjacent and arranged in the order of red, white, and blue.
In this question, we use integers 0, 1, and 2 to represent red, white, and blue, respectively.
Example 1:
Input: nums = [2,0,2,1,1,0]
Output: [0,0,1,1,2,2]
Example 2:
Input: nums = [2,0,1]
Output: [0,1,2]
Example 3:
Input: nums = [0]
Output: [0]
Example 4:
Input: nums = [1]
Output: [1]
prompt:
n == nums.length
1 <= n <= 300
nums[i] 为 0、1 或 2
Source: LeetCode
Problem solving
template
void sortColors(int* nums, int numsSize){
}
analysis
According to find a different thinking understanding, because this question asks for the order of red, white and blue to arrange the colors as close as possible, and this order happens to be the order of 012 instead, then we can simply understand the following questions It means to arrange the array elements as needed, so that it can also be arranged in the order of the elements and be as close together as possible to meet the requirements of the problem.
Original code
int cmp(int *a, int *b) {
return *a - *b;
}
void sortColors(int* nums, int numsSize){
qsort(nums, numsSize, sizeof(int), cmp);
return nums;
}
qsort is a sorting function in C language. It has also been used in the topic of array splitting . If you are interested, you can take a look at the introduction to the simple use of qsort()
operation result
