reference the tutorial of the solution;https://leetcode.com/articles/k-inverse-pairs-array/ very great explanation for 8 approaches, I only came up with the naive method and the recursive method (1) Define the subproblem dp[i][j] as the given integer i and the inverse pairs number j dp...
Given two integers n and k, find how many different arrays consist of numbers from 1 to n such that there are exactly k inverse pairs.We define an inverse pair as following: For ith and jth element in the array, if i < j and a[i] > a[j] then it's an inverse pair; Otherwise...
XOR and Favorite Number http://codeforces.com/contest/617/problem/E E. XOR and Favorite Number time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Bob has a favorite ...codeforces 617 E. XOR and Favorite Number(莫队) 题意: n个...