Haiyang HaiyangXu

HaiyangXu / CountInversions .cpp

Last active August 29, 2015 14:01

Algorithms: Design and Analysis, Part 1 Programming Question-1

	#include <iostream>
	#include <fstream>
	#include <vector>
	using namespace std;

	unsigned int merge(vector<int>&nums,int begin,int middle,int end)
	{
	vector<int> left(nums.begin()+begin,nums.begin()+middle);
	vector<int> right(nums.begin()+middle,nums.begin()+end);

HaiyangXu / Leet Code : Permutation Sequence .cpp

Created May 11, 2014 01:05

	class Solution {
	public:
	string getPermutation(int n, int k) {
	string re(n,'0');
	int fac=factorial(n);
	vector<int> vecNum(n,0);
	for(int i=1;i<=vecNum.size();++i)vecNum[i-1]=i;
	--k;// k=[0,(n-i)! ) ,inorder to get the right index
	for(int i=0;i<n;++i)
	{

HaiyangXu / Leet Code ：Next Permutation.cpp

Created May 10, 2014 13:03

	class Solution {
	public:
	void nextPermutation(vector<int> &num) {

	for(int i=num.size()-1;i-1>=0;--i)
	{
	if(num[i]>num[i-1])//找到最大的降序后缀 1[2]876530
	{
	for(int j=num.size()-1;j>=i;--j)
	{

HaiyangXu / Leet Code: Permutations II.cpp

Created May 9, 2014 02:15

	class Solution {
	public:
	vector<vector<int> > result;
	vector<vector<int> > permuteUnique(vector<int> &num) {
	permute(num,0);
	return result;
	}

	void permute(vector<int> &num,int index)
	{

HaiyangXu / Leet Code:Permutations.cpp

Last active August 29, 2015 14:01

	class Solution {
	public:
	vector<vector<int> > result;
	vector<vector<int> > permute(vector<int> &num) {
	permute(num,0);
	return result;
	}

	void permute(vector<int> &num,int index)
	{

HaiyangXu / Leet Code : Sort Colors.cpp

Created May 7, 2014 08:55

HaiyangXu / Leet Code : Median of Two Sorted Arrays .cpp

Created May 7, 2014 08:12

	class Solution {
	public:
	double findMedianSortedArrays(int A[], int m, int B[], int n) {
	int total=m+n;
	if(total&1)
	return findKth(A,m,B,n,total/2+1);
	else
	return (findKth(A,m,B,n,total/2)+findKth(A,m,B,n,total/2+1))/2;
	}

HaiyangXu / Leet Code: Valid Number.cpp

Created May 6, 2014 15:20