Preparing for the First Yard Coding Test

01 What algorithm should I use to solve this?
_01-1 Understanding Time Complexity Notation
_01-2 Using Time Complexity
__[000] Sort the numbers

02 How to catch logic errors in code?
_02-1 Why is debugging important?
_02-2 Debugging Use Case Study

Second Yard: Do It! Coding Test - Basics

03 Preview Coding Test Error Notes
_03-1 Resolving unexpected negative results
_03-2 Find the cause of the timeout and resolve it
_03-3 Solve by giving meaning to the index
_03-4 Understanding the importance of remainder operations
_03-5 Laying the foundation for alignment
_03-6 Mastering multi-condition sorting
_03-7 Using two-dimensional vectors

04 Data Structure
_04-1 Arrays, lists, and vectors
__[001] Find the sum of numbers
__[002] Finding the average
_04-2 Section Sum
__[003] Finding the sum of intervals 1
__[004] Finding the sum of intervals 2
__[005] Find the remainder
_04-3 Two pointers
__[006] Finding the sum of consecutive natural numbers
__[007] Jumong's command
__[008] Finding a 'good number'
_04-4 Sliding Window
__[009] DNA password
__[010] Finding the minimum
_04-5 Stacks and Queues
__[011] Creating a sequence with a stack
__[012] Find the number of okens
__[013] Card game
__[014] Implementing an absolute value heap

05 Sort
_05-1 Bubble sort
__[015] Sorting numbers 1
__[016] Bubble Sort Program 1
_05-2 Selection sort
__[017] Sort digits in descending order
_05-3 Insertion sort
__[018] Calculating ATM withdrawal times
_05-4 Quick sort
__[019] Find the Kth number
_05-5 Merge Sort
__[020] Sorting Numbers 2
__[021] Bubble Sort Program 2
_04-6 Radix alignment
__[022] Sorting numbers 3

06 Explore
_06-1 Depth-first search
__[023] Find the number of connected elements
__[024] Finding the mysterious prime number
__[025] Understanding Friendships
_06-2 Backtracking
__[026] N and M
__[027] Place N-Queen
__[028] Pasting colored paper
_06-3 Breadth-first search
__[029] DFS and BFS programs
__[030] Navigating the Maze
__[031] Finding the diameter of a tree
_06-4 Binary Search
__[032] Find the desired integer
__[033] Creating Blu-ray
__[034] Find the Kth number in the array

07 Greedy
_07-1 Greedy Algorithm
__[035] Find the minimum number of coins
__[036] Sorting cards
__[037] Create the maximum value by grouping numbers
__[038] Assign a conference room
__[039] Find the parentheses that create the minimum value

08 Number Theory
_08-1 Finding prime numbers
__[040] Finding prime numbers
__[041] Finding almost prime numbers
__[042] Finding the minimum among prime numbers and palindromes
__[043] Find a non-square number
_08-2 Euler Fee
__[044] Implementing Euler's Phi function
_08-3 Euclidean Algorithm
__[045] Finding the least common multiple
__[046] Finding the greatest common divisor
__[047] Making cocktails
_08-4 Extended Euclidean Algorithm
__[048] Ax + By = C

Third Yard: Do It! Coding Test - Practical Edition

09 Graph
_09-1 Graph representation
__[049] Find a city with a specific street
__[050] Hacking Efficiently
__[051] Identifying a bipartite graph
__[052] Find the amount of water
_09-2 Union Find
__[053] Representing sets
__[054] Planning a trip
__[055] I don't want to be a liar
_09-3 Topological sorting
__[056] Line up
__[057] Game Development
__[058] Finding the critical path
_09-4 Dijkstra
__[059] Finding the shortest path
__[060] Finding the minimum cost
__[061] Finding the Kth shortest path
_09-5 Bellman-Ford
__[062] Fast forward with the time machine
__[063] A Salesman's Worries
_09-6 Floyd-Warshall
__[064] Find the fastest bus route
__[065] Finding the path
__[066] Kevin Bacon's 6-Step Rule
_09-7 Minimum spanning tree
__[067] Finding the minimum spanning tree
__[068] Building a bridge
__[069] Helping the underprivileged

10 trees
_10-1 Understanding the Tree
__[070] Finding the parent of a tree
__[071] Finding the number of leaf nodes
_10-2 Try
__[072] Find string
_10-3 Binary Tree
__[073] Traversing the tree
_10-4 segment tree
__[074] Finding the sum of intervals 3
__[075] Finding the minimum 2
__[076] Finding the interval product
_10-5 Least common ancestor
__[077] Finding the Least Common Ancestor 1
__[078] Finding the Least Common Ancestor 2

11 combinations
_11-1 Learn about combinations
__[079] Finding the binomial coefficient 1
__[080] Finding the binomial coefficient 2
__[081] I will become the women's association president
__[082] Building a bridge
__[083] Take out the pebble
__[084] Finding the order of permutations
__[085] Dictionary search
__[086] Delivering a gift

12 Dynamic Programming
_12-1 Understanding Dynamic Programming
__[087] Make integer 1
__[088] Preparing to resign
__[089] Find Lee Chin-soo
__[090] Fill 2*N tiles
__[091] Find the number of steps
__[092] Finding the sum of consecutive integers
__[093] Find the longest common subsequence
__[094] Find the largest square
__[095] Find the building order
__[096] Let's try DDR
__[097] Finding the minimum number of matrix multiplication operations
__[098] Planning a salesman's itinerary
__[099] Find the longest increasing subsequence

13 Geometry
_13-1 Learning Geometry
__[100] Finding the direction of a line segment
__[101] Finding whether line segments intersect
__[102] Divide line segments into groups
__[103] Finding the area of ​​a polygon

Appendix A: Survival Strategy Notes for the Exam

_A-1 Analyzing the problem effectively
_A-2 Choosing the Right Algorithm
_A-3 Eliminating mistakes that determine elimination

Search

"100% reflecting the latest exam trends"
We've carefully selected only the algorithm areas that will appear in actual coding tests!

Based on the author's expertise gained from teaching coding tests for eight years, he has carefully selected areas that have been or will be included in actual IT company coding tests.
To help you focus solely on preparing for the coding test, this book excludes data structures and algorithms, which have a low probability of appearing on the test, and contains only the essential elements for passing.


"The most in Korea! 103 algorithm questions, covering all past exam questions."
It was further classified into three levels of importance.
Let's start with frequently asked and core questions!

We've included the largest collection of questions in Korea, allowing you to study all the past coding test questions from major IT companies without missing a single one.
By solving the 103 problems in this book, you will be fully prepared for the coding test.
Among these, 11 frequently appearing questions and 16 key questions were selected separately.
If you have an exam coming up and don't have time to study, start by solving frequently asked and key questions.

All 103 questions can be practiced on Baekjoon Online Judge.
Practice once in a book and once online to double your learning effect!

All the problems in the book were carefully selected from Baekjoon Online Judge, Korea's largest algorithm problem book website.
After studying problem-solving methods in the book, try solving the problems yourself on 'Baekjoon Online Judge'.
As you grade and edit your own code, your coding skills will improve rapidly, and you'll also gain your own template code that can be used for each core algorithm type.

"Practice as if it were real with the four-step problem-solving habit."
Coding tests are a race against time! Practice like you're on the real thing and overcome them!

As with any other exam, coding tests require you to use the given time wisely to solve the problems.
It contains systematic problem-solving methods to avoid mistakes due to time constraints.
This book solves algorithmic problems in four steps: [Analyze the problem → Solve it manually → Write pseudocode → Implement the code].
If you develop the habit of solving problems like this, you will be able to demonstrate your skills to the fullest without making any mistakes on the actual test.

“Passing and failing are just a sheet of paper apart!”
Even the smallest tips that can determine your exam results!

There are many cases where people fail exams due to small mistakes.
The author, who has taught coding tests for eight years, has personally selected common mistakes made during the test and included tips for reducing them in [Preview Coding Test Error Notes].
The appendix includes [Testing Center Survival Strategy Notes], which will help you review your passing strategies right up until the very end of the exam.
Studying with this book will ensure that all your hard work is not in vain and you pass the coding test!

“Set a goal and study systematically on your own!”
Two study plans are provided: a 30-day course for beginners and a 3-day course for exam preparation.

This book provides a study plan so that you can study systematically on your own.
Write down your own target dates on your study schedule and study.
If you want to study coding tests step by step, we recommend the '30-day course'. If you want to solve only important problems before the exam, we recommend the '3-day course'.
Completed example files are also available on the Aegis Publishing website and the author's GitHub.
Study without any difficulties by comparing your own code with example files!
ㆍ Easy Publishing website: www.easyspub.co.kr → Click [Data Room] → Search for book title
Author's GitHub: https://github.com/doitcodingtest/C

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Share difficult content with readers who have similar concerns.
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