
hiho week 206
This week we will solve the problem "Guess Number with Lower or Higher Hints". Solution is here。
121

hiho week 165
This week we will solve the problem "Separating Same Characters". Solution is here.
334

hiho week 152
This week we will solve the problem "Difference of Interval Collections". Solution is here.
252

hiho week 125
This week let's learn GeoHash's encoding and decoding with Little Hi and Little Ho.
153

hiho week 118
This week let's solve the problem of minimum path cover in DAG using max flow algorithm.
1068

hiho week 114
This week we will learn how to solve problem "Image Encryption".Here is the solution.
295

hiho week 112
This week we will learn how to solve problem "Total Highway Distance".Here is the solution.
443

hiho week 111
This week we will learn how to solve problem "Farthest Point".Here is the solution.
456

hiho week 110
This week we will learn how to solve problem "Increase Charisma Points".Here is the solution.
465

hiho week 109
This week we will learn how to solve problem "Tower Defense Game".Here is the solution.
438

hiho week 108
This week we will learn how to solve problem "Memory Allocating Algorithm".Here is the solution.
295

hiho week 107
This week we will learn how to solve problem "Give My Text Back".Here is the solution.
535

hiho week 106
This week learn Size Balanced Tree, a kind of balanced search tree with amortized time O(logn) for each operation.
424

hiho week 104
This week learn Splay Tree, a kind of balanced search tree with amortized time O(logn) for each operation.
220

hiho week 103
This week learn Treap, a kind of balanced search tree whose expected depth is O(logn).
252

hiho week 102
This week solve the sudoku problem with Little Hi and Little Ho, using dancing links.
235

hiho week 101
Learn dancing links with Little Hi and Little Ho, the technique suggested by Donald Knuth to efficiently implement some search algorithms.
397

hiho week 100
This week Little Hi and Little Ho try to solve the famous 8puzzle problem with the famous A* algorithm.
432

hiho week 98
This week Little Hi and Little Ho try to solve an arithmetical card game  24 points.
433

hiho week 96
Learn Euler's totient function or Euler's phi function with Little Hi and Little Ho.
673

hiho week 81
This week we will solve the problem "Professor Q's Software". Here is the solution.
133

hiho week 79
This week we will solve the problem "Troublesome Power Supply". Here is the solution.
158

hiho week 78
This week we will solve the problem "Shortest Proper Prefix". Here is the solution.
288

hiho week 64
This week we will solve the problem "Rightclick Context Menu". Here is the solution.
874

hiho week 60
This week we will solve the problem "String Matching Content Length". Here is the solution.
587

hiho week 53
After suffering from computer virus, Little Hi and Little Ho's school is rebuilding the campus network.
396

hiho week 52
After suffering from computer virus, Little Hi and Little Ho's school is rebuilding the campus network.
214

hiho week 50
After having collected all items, little Hi and little Ho have to face to a new problem.
436

hiho week 40
The 5th week of learning divide and conquer algorithm. Let's study a new divide and conquer algorithm.
1627

hiho week 39
The 4th week of learning divide and conquer algorithm. Let's see a classic problem.
2159

hiho week 38
This week let's study a very useful application of binary search, reducing optimization problems to decision problems.
420

hiho week 36
After having studied bipartite graph, we will start a new series about divide and conquer algorithms.
242

hiho week 33
The adventure of Little Hi and Little Ho will continue after the Spring Festival. Now let's enjoy the holidays.
140

hiho week 32
"Little Hi!!! Where's the perfect solution you promised?!!! What do you mean GUESS in this last step!" little Ho says, with rage filled up his mind.
133

hiho week 31
"Zero ... zero each time! It would be so convenient if they all reverse in one move as in computer!" little says, wite anger on his face.
313

hiho week 30
"If ... I died after this step, little Hi, please take care of my parents ..." little Ho says, with tears in his eyes.
387

hiho week 29
These is no love without reason, and there is no reduction of time comlexity without reason!
458

hiho week 25
Algorithms... well, some of them, is just simply traversal and ... some improvement!
726

hiho week 24
Well, right! Ten times of an algorithm with time comlexity of O(N^2) is good enough to take over the algorithm with time comlexity of O(N^3)! But, what if I tell you this algorithm is only writen in 5 lines?
807

hiho week 20
Segmenttree seems to be too much for RMQ problem ? Let's see some more powerful usage!
214

hiho week 19
Less is more, far is near  will ST algorithm reborn after calculate less intervals?
317

hiho week 18
SImple modification make easy problem really complicated ! What's the secrets that behind the RMQ problem ?!
468

hiho Week 17
It is so embarrassing that Hi and Ho applied an advanced LCA algorithm but nothing goes better. How will Hi and Ho deal with this?
394

hiho Week 15
In order to cover the uesless of algorithm, should we spent thounds to buy servers? No! Ho says so.
1653

hiho Week 13
"We came from the same ancient!", people having same last name will say so. But which ancient is the nearest one? Hi and Ho will let you know!
460

hiho Week 12
The painting on Ho's toy tree has been erased due to Ho's endless rub! What will Ho do ?
337

hiho Week 11
"Diameter of tree", such a classic problem must be collected in our sets of tree problems that represents "Recursion"! Wanna know how to solve it?
433

hiho Week 10
Calculating binary tree postorder traversal from given preorder and inorder traversal is just shown up in the online test of Alibaba!~ Just come and see how Hi and Ho solve it!
639

hiho Week 9
"State Compression" is useful tool to deal with many circumstances. Let's see how Hi and Ho put their cakes!
362

hiho Week 8
Sometimes the division of state will be uncertain, and in this case, the state compression will help a lot!
541

hiho Week 7
In another parallel universe, the story of Hi and Ho has been changed magically! What's variants of "knapsack" problem? Can we eat it? Does it tasty? And how can we eat it?
913

hiho Week 6
The "0/1 knapsack" problem is not only a simply dynamic programming model! Let's see how Ho use it to solve his problem~
538

hiho Week 5
You should already know the problem "Triangle of numbers", but as the Confucius says "Reviewing leads to new". So why not come and see how Hi and Ho solve it?
445

hiho Week 4
Do you still remember the problem that Mr.Hexie presented in Hiho! Week 3? This time Hi and Ho will end it !
617

hiho Week 3
Pattern Matching is an everlasting topic in String Processing, and KMP algorithm is the brightest one with no doubt! So come and learn it with Hi and Ho~
669

hiho Week 2
String autocompletion is important both in input method and search engine, but do you know how to implemtent it?
1624

hiho Week 1
You must be familiar with such a classic problem as "The longest palindrome"? But do you know the 3 kinds of way to solve it? Just have a try!
1162