How to find the reverse pairs in arrays in golang
This article will explain in detail how to find the reverse order pair in the array in golang. The content of the article is of high quality. Therefore, Xiaobian shares it with you as a reference. I hope you will have a certain understanding of relevant knowledge after reading this article.
Two numbers in an array form an inverted pair if the first number is greater than the second. Enter an array and find the total number of inverted pairs in the array.
Example 1:
Input: [7,5,6,4]
Output: 5
Limitations:
0 4, indicating that all elements after 5 can form an inverse pair with 4; therefore sum +=(leftLen - i);
5
< 6,正常排序,不做处理 7 >6, indicating that all elements after 7 can form an inverse pair with 6; therefore sum +=(leftLen - i);
7, normal sorting, no processing
code implementation
func reversePairs(nums []int) int { /* sum:=0 for i:=0;i