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ducalpha / LogErrno.cc

Created April 15, 2016 07:51

Logging errors

	void LogError(const char *fmt, ...) {
	va_list vlist;
	va_start(vlist, fmt);

	const size_t kLogMessageLength = 128;
	char log_message[kLogMessageLength];
	vsnprintf(log_message, kLogMessageLength, fmt, vlist);

	LogError(log_message);
	va_end(vlist);

ducalpha / verify_preorder_serialization.cpp

Created March 23, 2016 15:20

Verify Preorder Serialization of a Binary Tree

	// https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/
	class Solution {
	public:
	bool isValidSerialization(string preorder) {
	if (preorder.empty())
	return true;

	int i = preorder.length() - 1;
	int stack_size = 0;
	while (i >= 0) {

ducalpha / triplet_increasing_subarray.cpp

Created March 22, 2016 18:50

Check whether or not an array contains an increasing triplet

	// https://leetcode.com/problems/increasing-triplet-subsequence/
	class Solution {
	public:
	bool increasingTriplet(vector<int>& nums) {
	if (nums.size() < 3)
	return false;
	int l = 0, r = nums.size() - 1, u = 0;
	// increase l as much as possible
	while (l < nums.size() - 1 && nums[l] >= nums[l + 1])
	++l;

ducalpha / largest_bst.cpp

Created February 26, 2016 11:52

Given a binary tree, find the largest subtree which is a Binary Search Tree (BST), where largest means subtree with largest number of nodes in it.

	/**
	* https://leetcode.com/problems/largest-bst-subtree/
	* Definition for a binary tree node.
	* struct TreeNode {
	* int val;
	* TreeNode *left;
	* TreeNode *right;
	* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
	* };
	*/

ducalpha / test_css_position.html

Created February 21, 2016 07:23

test css position

ducalpha / iframe_a_target.html

Created February 21, 2016 02:36

iframe and a tag target example

	<html><head>
	</head>
	<body>
	<iframe src="http://www.w3schools.com/" name="A"><p> This my first iframe</p></iframe>
	<iframe src="http://cps.kaist.ac.kr/" name="B"><p> This my second iframe</p></iframe>
	<iframe src="http://www.example.com/" name="C"><p> This my third iframe</p></iframe>

	<a href="http://www.kaist.ac.kr" target="B">Change B</a>

ducalpha / convert_min_first_to_max_first.cpp

Created January 29, 2016 12:04

Convert a min-first BST to a max-first BST

	#include <my_epi/common.h>

	template <typename T>
	struct BTNode {
	T data;
	shared_ptr<BTNode<T>> left, right;
	};

	typedef BTNode<int> NodeType;

ducalpha / find_min_time_period.cpp

Created January 4, 2016 00:29

	int FindMinTimePeriod(const vector<int>& tasks, int K) {
	unordered_map<int, int> task_to_last_time;
	int cur_time = 0;
	for (int i = 0; i < tasks.size(); ++i) {
	int cur_task = tasks[i];
	auto it = task_to_last_time.find(cur_task);
	if (it != task_to_last_time.end()) {
	cur_time = max(cur_time, it->second + K + 1);
	it->second = cur_time;
	} else {

ducalpha / is_valid_schedule.cpp

Created January 4, 2016 00:27

Check valid schedule

	struct Meeting {
	int start, end;
	};
	struct CompareMeeting {
	bool operator()(const Meeting& a, const Meeting& b) const {
	if (a.start == b.start) return a.end < b.end;
	return a.start < b.start;
	}
	};
	bool IsValidSchedule(vector<Meeting> meetings) {

ducalpha / find_longest_subarray_closest_to_k.cpp

Created December 18, 2015 14:36

find longest subarray closest/equal to k

	pair<int, int> FindSubarrayClosestToK(const vector<int>& a, int k) {
	pair<int, int> range{0, -1};

	if (a.empty()) return range;

	map<int, int> sum_to_idx;
	int sum = 0;
	int min_diff = k;
	sum_to_idx.emplace(0, -1); // S[-1] = 0 so push 0, -1 here!
	for (int i = 0; i < a.size(); ++i) {