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_posts/2023-01-01-Algorithm.md

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+---
+
+title: Algorithm
+
+date: 2023-01-01
+categories: [Algorithm]
+tags: [Algorithm]
+layout: post
+toc: true
+math: true
+mermaid: true
+
+---
+
+# DataStructure
+
+## 괄호 - boj.kr/9012
+
+```kotlin
+import java.io.BufferedReader
+import java.io.BufferedWriter
+import java.io.InputStreamReader
+import java.io.OutputStreamWriter
+import java.util.*
+
+private val br = BufferedReader(InputStreamReader(System.`in`))
+private val bw = BufferedWriter(OutputStreamWriter(System.out))
+
+fun main() {
+    val t = br.readLine().toInt()
+
+    repeat(t) {
+        val input = br.readLine()
+        val stack: Stack<String> = Stack()
+
+        repeat(input.length) {
+            val current = input.substring(it, it + 1)
+
+            if (current == "(") {
+                stack.push(current)
+            } else if (current == ")") {
+                if (stack.isNotEmpty()) {
+                    if (stack.peek() == "(") {
+                        stack.pop()
+                    }
+                } else {
+                    stack.push(current)
+                }
+            }
+        }
+
+        if (stack.isEmpty()) {
+            println("YES")
+        } else {
+            println("NO")
+        }
+    }
+}
+```
+
+## 균형잡힌 세상 - boj.kr/4949
+
+```kotlin
+import java.io.BufferedReader
+import java.io.BufferedWriter
+import java.io.InputStreamReader
+import java.io.OutputStreamWriter
+import java.util.*
+
+private val br = BufferedReader(InputStreamReader(System.`in`))
+private val bw = BufferedWriter(OutputStreamWriter(System.out))
+
+fun main() {
+
+    while (true) {
+        val input = br.readLine()
+        if (input == ".") break
+
+        val stack = Stack<Char>()
+        var isBalanced = true
+
+        for (char in input) {
+            when (char) {
+                '(', '[' -> stack.push(char)
+                ')' -> {
+                    if (stack.isEmpty() || stack.pop() != '(') {
+                        isBalanced = false
+                        break
+                    }
+                }
+
+                ']' -> {
+                    if (stack.isEmpty() || stack.pop() != '[') {
+                        isBalanced = false
+                        break
+                    }
+                }
+            }
+        }
+
+        if (isBalanced && stack.isEmpty()) {
+            println("yes")
+        } else {
+            println("no")
+        }
+    }
+}
+```
+
+## 덱 - boj.kr/10866
+
+```kotlin
+import java.io.BufferedReader
+import java.io.BufferedWriter
+import java.io.InputStreamReader
+import java.io.OutputStreamWriter
+
+private val br = BufferedReader(InputStreamReader(System.`in`))
+private val bw = BufferedWriter(OutputStreamWriter(System.out))
+
+fun main() {
+    val n = br.readLine().toInt()
+    val deque = ArrayDeque<Int>()
+
+    repeat(n) {
+        val input = br.readLine().split(" ")
+        when (input[0]) {
+            "push_back" -> deque.addLast(input[1].toInt())
+            "pop_back" -> bw.write(if (deque.isEmpty()) "-1\n" else "${deque.removeLast()}\n")
+            "push_front" -> deque.addFirst(input[1].toInt())
+            "pop_front" -> bw.write(if (deque.isEmpty()) "-1\n" else "${deque.removeFirst()}\n")
+            "front" -> bw.write(if (deque.isEmpty()) "-1\n" else "${deque.first()}\n")
+            "back" -> bw.write(if (deque.isEmpty()) "-1\n" else "${deque.last()}\n")
+            "size" -> bw.write("${deque.size}\n")
+            "empty" -> bw.write(if (deque.isEmpty()) "1\n" else "0\n")
+        }
+    }
+    br.close()
+    bw.close()
+}
+```
+
+## 수찾기 - boj.kr/1920
+
+```kotlin
+import java.io.BufferedReader
+import java.io.BufferedWriter
+import java.io.InputStreamReader
+import java.io.OutputStreamWriter
+
+private val br = BufferedReader(InputStreamReader(System.`in`))
+private val bw = BufferedWriter(OutputStreamWriter(System.out))
+
+
+fun main() {
+    val n = br.readLine().toInt()
+    val array = br.readLine().split(" ").map { it.toInt() }.toHashSet()
+
+    val m = br.readLine().toInt()
+    val target = br.readLine().split(" ").map { it.toInt() }
+
+    for (value in target) {
+        if (value in array) {
+            println(1)
+        } else {
+            println(0)
+        }
+    }
+}
+```
+
+# String
+
+# BruteForce
+
+# Implementation
+
+# Greedy
+
+# Back-Tracking
+
+# Graph
+
+# Dijkstra
+
+# Divide And Conquer
+
+# DP