diff --git "a/9-kyo-hwang/Brute Force/2024 KAKAO WINTER INTERNSHIP \353\254\270\354\240\234 3 \354\243\274\354\202\254\354\234\204 \352\263\240\353\245\264\352\270\260.cpp" "b/9-kyo-hwang/Brute Force/2024 KAKAO WINTER INTERNSHIP \353\254\270\354\240\234 3 \354\243\274\354\202\254\354\234\204 \352\263\240\353\245\264\352\270\260.cpp"
new file mode 100644
index 0000000..518173e
--- /dev/null
+++ "b/9-kyo-hwang/Brute Force/2024 KAKAO WINTER INTERNSHIP \353\254\270\354\240\234 3 \354\243\274\354\202\254\354\234\204 \352\263\240\353\245\264\352\270\260.cpp"	
@@ -0,0 +1,71 @@
+#include <string>
+#include <vector>
+#include <algorithm>
+#include <unordered_map>
+
+using namespace std;
+
+void CountEachComboSums(const vector<vector<int>>& Dices, const vector<int>& SelectedDices, unordered_map<int, int>& DiceComboMap, int ComboSum = 0, int DiceIndex = 0)
+{
+    if(DiceIndex == SelectedDices.size())
+    {
+        DiceComboMap[ComboSum] += 1;
+        return;
+    }
+
+    for(const int& DicePip : Dices[SelectedDices[DiceIndex]])
+    {
+        CountEachComboSums(Dices, SelectedDices, DiceComboMap, ComboSum + DicePip, DiceIndex + 1);
+    }
+}
+
+vector<int> solution(vector<vector<int>> Dice) 
+{
+    const int NumDice = Dice.size();
+    vector<bool> IsADice(NumDice / 2, false);
+    IsADice.insert(IsADice.end(), NumDice / 2, true);
+
+    int MaxCntOfAWins = 0;
+    vector<int> Answer;
+    do 
+    {
+        vector<int> A, B;
+        for(int i = 0; i < NumDice; ++i)
+        {
+            IsADice[i] ? A.emplace_back(i) : B.emplace_back(i);
+        }
+
+        unordered_map<int, int> AComboMap, BComboMap;
+        CountEachComboSums(Dice, A, AComboMap);
+        CountEachComboSums(Dice, B, BComboMap);
+
+        vector<pair<int, int>> AComboVector(AComboMap.begin(), AComboMap.end());
+        vector<pair<int, int>> BComboVector(BComboMap.begin(), BComboMap.end());
+
+        sort(AComboVector.begin(), AComboVector.end());
+        sort(BComboVector.begin(), BComboVector.end());
+
+        int CntOfAWins = 0;
+        for(const auto& [AComboSum, AComboCnt] : AComboVector)
+        {
+            for(const auto& [BComboSum, BComboCnt] : BComboVector)
+            {
+                if(BComboSum >= AComboSum)
+                {
+                    break;
+                }
+
+                CntOfAWins += AComboCnt * BComboCnt;
+            }
+        }
+
+        if(CntOfAWins > MaxCntOfAWins)
+        {
+            MaxCntOfAWins = CntOfAWins;
+            Answer = A;
+        }
+    } while(next_permutation(IsADice.begin(), IsADice.end()));
+
+    transform(Answer.begin(), Answer.end(), Answer.begin(), [](int& i) { return i + 1; });
+    return Answer;
+}
\ No newline at end of file
diff --git "a/9-kyo-hwang/Graph Traversal/1039 \352\265\220\355\231\230.cpp" "b/9-kyo-hwang/Graph Traversal/1039 \352\265\220\355\231\230.cpp"
new file mode 100644
index 0000000..d7064ef
--- /dev/null
+++ "b/9-kyo-hwang/Graph Traversal/1039 \352\265\220\355\231\230.cpp"	
@@ -0,0 +1,49 @@
+#include <iostream>
+#include <string>
+#include <algorithm>
+#include <unordered_set>
+
+using namespace std;
+
+string N; int K;
+unordered_set<int> Visited[11];
+
+int DFS(string Num = N, int Depth = 0)
+{
+    if(Visited[Depth].find(stoi(Num)) != Visited[Depth].end())
+    {
+        return -1;
+    }
+    else if(Depth == K)
+    {
+        return stoi(Num);
+    }
+    else
+    {
+        Visited[Depth].emplace(stoi(Num));
+        int MaxNum = -1;
+        for(int i = 0; i < N.size() - 1; ++i)
+        {
+            for(int j = i + 1; j < N.size(); ++j)
+            {
+                if(i == 0 && Num[j] == '0')
+                {
+                    continue;
+                }
+                string TmpNum = Num;
+                swap(TmpNum[i], TmpNum[j]);
+                
+                MaxNum = max(MaxNum, DFS(TmpNum, Depth + 1));
+            }
+        }
+        return MaxNum;
+    }
+}
+
+int main()
+{
+    cin.tie(nullptr)->sync_with_stdio(false);
+    cin >> N >> K;
+    cout << DFS();
+    return 0;
+}
\ No newline at end of file
diff --git "a/9-kyo-hwang/Prefix Sum/2022 KAKAO BLIND RECRUITMENT \355\214\214\352\264\264\353\220\230\354\247\200 \354\225\212\354\235\200 \352\261\264\353\254\274.cpp" "b/9-kyo-hwang/Prefix Sum/2022 KAKAO BLIND RECRUITMENT \355\214\214\352\264\264\353\220\230\354\247\200 \354\225\212\354\235\200 \352\261\264\353\254\274.cpp"
new file mode 100644
index 0000000..e8b9f7c
--- /dev/null
+++ "b/9-kyo-hwang/Prefix Sum/2022 KAKAO BLIND RECRUITMENT \355\214\214\352\264\264\353\220\230\354\247\200 \354\225\212\354\235\200 \352\261\264\353\254\274.cpp"	
@@ -0,0 +1,86 @@
+#include <string>
+#include <vector>
+
+using namespace std;
+
+struct FSkill
+{
+    int Type, R1, C1, R2, C2, Degree;
+    
+    FSkill(const vector<int>& InSkill) : Type(InSkill[0]), R1(InSkill[1]), C1(InSkill[2]), R2(InSkill[3]), C2(InSkill[4]), Degree(InSkill[5]) { }
+};
+
+enum class ESkillType
+{
+    NONE,
+    ATTACK,
+    HEAL,
+};
+
+vector<vector<int>> GetWeightMatrix(const int N, const int M, const vector<vector<int>>& InSkills)
+{
+    vector WeightMatrix(N + 1, vector(M + 1, 0));
+    for(const vector<int>& InSkill : InSkills)
+    {
+        FSkill Skill(InSkill);
+        if(Skill.Type == static_cast<int>(ESkillType::ATTACK))
+        {
+            WeightMatrix[Skill.R1][Skill.C1] -= Skill.Degree;
+            WeightMatrix[Skill.R2 + 1][Skill.C2 + 1] -= Skill.Degree;
+            
+            WeightMatrix[Skill.R1][Skill.C2 + 1] += Skill.Degree;
+            WeightMatrix[Skill.R2 + 1][Skill.C1] += Skill.Degree;
+        }
+        else if(Skill.Type == static_cast<int>(ESkillType::HEAL))
+        {
+            WeightMatrix[Skill.R1][Skill.C1] += Skill.Degree;
+            WeightMatrix[Skill.R2 + 1][Skill.C2 + 1] += Skill.Degree;
+            
+            WeightMatrix[Skill.R1][Skill.C2 + 1] -= Skill.Degree;
+            WeightMatrix[Skill.R2 + 1][Skill.C1] -= Skill.Degree;
+        }
+    }
+    
+    for(int i = 0; i <= N; ++i)
+    {
+        for(int j = 0; j < M; ++j)
+        {
+            WeightMatrix[i][j + 1] += WeightMatrix[i][j];
+        }
+    }
+    
+    for(int j = 0; j <= M; ++j)
+    {
+        for(int i = 0; i < N; ++i)
+        {
+            WeightMatrix[i + 1][j] += WeightMatrix[i][j];
+        }
+    }
+       
+    return WeightMatrix;
+}
+
+int solution(vector<vector<int>> Board, vector<vector<int>> Skills) 
+{
+    const int N = Board.size(), M = Board[0].size();
+    vector<vector<int>> WeightMatrix = GetWeightMatrix(N, M, Skills);
+    
+    for(int i = 0; i < N; ++i)
+    {
+        for(int j = 0; j < M; ++j)
+        {
+            Board[i][j] += WeightMatrix[i][j];
+        }
+    }
+    
+    int Answer = 0;
+    for(const vector<int>& Row : Board)
+    {
+        for(const int& Col : Row)
+        {
+            Answer += (Col > 0);
+        }
+    }
+    
+    return Answer;
+}
\ No newline at end of file
diff --git a/9-kyo-hwang/README.md b/9-kyo-hwang/README.md
index f80a106..8b68b69 100644
--- a/9-kyo-hwang/README.md
+++ b/9-kyo-hwang/README.md
@@ -26,4 +26,7 @@
 | 23차시 | 2024.1.24  | Disjoint Set               | [표 병합](https://school.programmers.co.kr/learn/courses/30/lessons/150366)        | [#81](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/81) |
 | 24차시 | 2024.1.28  | Tree                       | [표현 가능한 이진트리](https://school.programmers.co.kr/learn/courses/30/lessons/150367)        | [#92](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/92) |
 | 25차시 | 2024.2.8   | Brute Force                | [조이스틱](https://school.programmers.co.kr/learn/courses/30/lessons/42860)        | [#99](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/99) |
-| 26차시 | 2024.2.11  | Brute Force                | [주사위 고르기](https://school.programmers.co.kr/learn/courses/30/lessons/258709)        | [#104](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/104) |
\ No newline at end of file
+| 26차시 | 2024.2.11  | Brute Force                | [주사위 고르기](https://school.programmers.co.kr/learn/courses/30/lessons/258709)        | [#104](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/104) |
+| 27차시 | 2024.2.14  | Graph Traversal            | [1039 교환](https://www.acmicpc.net/problem/1039)        | [#105](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/105) |
+| 28차시 | 2024.2.19  | Simulation                 | [SWEA 5644 무선 충전](https://swexpertacademy.com/main/code/problem/problemDetail.do?contestProbId=AWXRDL1aeugDFAUo&categoryId=AWXRDL1aeugDFAUo&categoryType=CODE&problemTitle=5644&orderBy=FIRST_REG_DATETIME&selectCodeLang=ALL&select-1=&pageSize=10&pageIndex=1)        | [#111](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/111) |
+| 29차시 | 2024.2.22  | Prefix Sum                 | [파괴되지 않은 건물](https://school.programmers.co.kr/learn/courses/30/lessons/92344)        | [#114](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/114) |
diff --git "a/9-kyo-hwang/Simulation/SWEA 5644 \353\254\264\354\204\240 \354\266\251\354\240\204.cpp" "b/9-kyo-hwang/Simulation/SWEA 5644 \353\254\264\354\204\240 \354\266\251\354\240\204.cpp"
new file mode 100644
index 0000000..103b055
--- /dev/null
+++ "b/9-kyo-hwang/Simulation/SWEA 5644 \353\254\264\354\204\240 \354\266\251\354\240\204.cpp"	
@@ -0,0 +1,94 @@
+#include <iostream>
+#include <vector>
+
+using namespace std;
+using Loc = pair<int, int>;
+
+#define x first
+#define y second
+
+Loc operator+(const Loc &a, const Loc &b) { return {a.x + b.x, a.y + b.y}; }
+
+struct BC {
+  int Index, X, Y, C, P;
+
+  BC() : Index(-1), X(-1), Y(-1), C(-1), P(-1) {}
+  BC(int inIndex, int inX, int inY, int inC, int inP)
+      : Index(inIndex), X(inX), Y(inY), C(inC), P(inP) {}
+
+  [[nodiscard]] inline int D(const Loc &loc) const {
+    return abs(X - loc.x) + abs(Y - loc.y);
+  }
+};
+
+int main() {
+  cin.tie(nullptr)->sync_with_stdio(false);
+  const vector<Loc> offset = {{}, {-1, 0}, {0, 1}, {1, 0}, {0, -1}};
+
+  int M, A;
+  vector<int> aMvTrajectories, bMvTrajectories;
+  vector<BC> BCs;
+  Loc aLoc, bLoc;
+
+  auto Input = [&]() {
+    cin >> M >> A;
+    aMvTrajectories.assign(M + 1, 0);
+    bMvTrajectories.assign(M + 1, 0);
+    BCs.assign(A, {});
+
+    for (int T = 1; T <= M; ++T) {
+      cin >> aMvTrajectories[T];
+    }
+    for (int T = 1; T <= M; ++T) {
+      cin >> bMvTrajectories[T];
+    }
+
+    int bcCnt = 0;
+    for (auto &[Index, X, Y, C, P] : BCs) {
+      cin >> Y >> X >> C >> P;
+      Index = bcCnt++;
+    }
+
+    aLoc = {1, 1};
+    bLoc = {10, 10};
+  };
+
+  auto Charge = [&]() {
+    int maxCharge = 0;
+    for (const auto &aBC : BCs) {
+      const int aDist = aBC.D(aLoc);
+      const int aAmt = aDist <= aBC.C ? aBC.P : 0;
+
+      for (const auto &bBC : BCs) {
+        const int bDist = bBC.D(bLoc);
+        const int bAmt = bDist <= bBC.C ? bBC.P : 0;
+
+        const int curCharge =
+            (aBC.Index != bBC.Index ? aAmt + bAmt : max(aAmt, bAmt));
+
+        maxCharge = max(maxCharge, curCharge);
+      }
+    }
+    return maxCharge;
+  };
+
+  auto Move = [&]() {
+    int totalCharge = 0;
+    for (int time = 0; time <= M; ++time) {
+      aLoc = aLoc + offset[aMvTrajectories[time]];
+      bLoc = bLoc + offset[bMvTrajectories[time]];
+
+      totalCharge += Charge();
+    }
+    return totalCharge;
+  };
+
+  int T;
+  cin >> T;
+  for (int tc = 1; tc <= T; ++tc) {
+    Input();
+    cout << "#" << tc << " " << Move() << "\n";
+  }
+
+  return 0;
+}
\ No newline at end of file
diff --git "a/Dolchae/DFS&BFS/2644 \354\264\214\354\210\230\352\263\204\354\202\260.py" "b/Dolchae/DFS&BFS/2644 \354\264\214\354\210\230\352\263\204\354\202\260.py"
new file mode 100644
index 0000000..d515960
--- /dev/null
+++ "b/Dolchae/DFS&BFS/2644 \354\264\214\354\210\230\352\263\204\354\202\260.py"	
@@ -0,0 +1,28 @@
+n = int(input())
+a,b = map(int, input().split())
+node_num = int(input())
+graph = [[] for _ in range(n+1)]
+visited = [False] * (n+1)
+result = []
+
+for _ in range(node_num):
+  x, y = map(int, input().split())
+  graph[x].append(y)
+  graph[y].append(x)
+
+def dfs(v, num):
+  num += 1
+  visited[v] = True
+
+  if v == b:
+    result.append(num)
+
+  for i in graph[v]:
+    if not visited[i]:
+      dfs(i, num)
+
+dfs(a, 0)
+if len(result) == 0:
+  print(-1)
+else:
+  print(result[0]-1)
\ No newline at end of file
diff --git a/Dolchae/README.md b/Dolchae/README.md
index 2df4037..bda8bb4 100644
--- a/Dolchae/README.md
+++ b/Dolchae/README.md
@@ -28,4 +28,7 @@
 | 24차시| 2024.01.29 | 수학  | [2108 통계학](https://www.acmicpc.net/problem/2108) | [#87](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/87) |
 | 25차시| 2024.02.01 | DP  | [1535 안녕](https://www.acmicpc.net/problem/1535) | [#89](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/89) |
 | 26차시| 2024.02.05 | 구현  | [18110 solved.ac](https://www.acmicpc.net/problem/18110) | [#93](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/93) |
-| 27차시| 2024.02.08 | 정렬  | [1302 베스트셀러](https://www.acmicpc.net/problem/1302) | [#97](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/97) |
\ No newline at end of file
+| 27차시| 2024.02.08 | 정렬  | [1302 베스트셀러](https://www.acmicpc.net/problem/1302) | [#97](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/97) |
+| 28차시| 2024.02.15 | 이진 탐색  | [6236 용돈 관리](https://www.acmicpc.net/problem/1302) | [#107](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/107) |
+| 29차시| 2024.02.19 | 브루트포스  | [2961 도영이가 만든 맛있는 음식](https://www.acmicpc.net/problem/2961) | [#109](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/109) |
+| 30차시| 2024.02.22 | DFS  | [2644 촌수계산](https://www.acmicpc.net/problem/2961) | [#112](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/112) |
\ No newline at end of file
diff --git "a/Dolchae/\353\270\214\353\243\250\355\212\270\355\217\254\354\212\244/2961 \353\217\204\354\230\201\354\235\264\352\260\200 \353\247\214\353\223\240 \353\247\233\354\236\210\353\212\224 \354\235\214\354\213\235n.py" "b/Dolchae/\353\270\214\353\243\250\355\212\270\355\217\254\354\212\244/2961 \353\217\204\354\230\201\354\235\264\352\260\200 \353\247\214\353\223\240 \353\247\233\354\236\210\353\212\224 \354\235\214\354\213\235n.py"
new file mode 100644
index 0000000..7404c9e
--- /dev/null
+++ "b/Dolchae/\353\270\214\353\243\250\355\212\270\355\217\254\354\212\244/2961 \353\217\204\354\230\201\354\235\264\352\260\200 \353\247\214\353\223\240 \353\247\233\354\236\210\353\212\224 \354\235\214\354\213\235n.py"	
@@ -0,0 +1,23 @@
+import sys
+from itertools import combinations
+input = sys.stdin.readline
+
+n = int(input())
+
+ingrid = [[0 for _ in range(2)] for _ in range(n)]
+for i in range(n):
+    ingrid[i][0],ingrid[i][1] = map(int,input().split())
+
+ans = abs(ingrid[0][0] - ingrid[0][1])
+for i in range(1,n+1): #1
+    for comb in combinations(ingrid,i): #2
+        print(comb)
+        sour, bitter = 1,0
+        for j in range(i): #3
+            sour *= comb[j][0]
+            bitter += comb[j][1]
+        now_diff = abs(sour-bitter)
+        if now_diff < ans: 
+            ans = now_diff
+
+print(ans)
diff --git "a/Dolchae/\354\235\264\354\247\204 \355\203\220\354\203\211/6236 \354\232\251\353\217\210 \352\264\200\353\246\254.py" "b/Dolchae/\354\235\264\354\247\204 \355\203\220\354\203\211/6236 \354\232\251\353\217\210 \352\264\200\353\246\254.py"
new file mode 100644
index 0000000..6c19126
--- /dev/null
+++ "b/Dolchae/\354\235\264\354\247\204 \355\203\220\354\203\211/6236 \354\232\251\353\217\210 \352\264\200\353\246\254.py"	
@@ -0,0 +1,36 @@
+import sys
+
+input = sys.stdin.readline
+
+n, m = map(int, input().split())
+
+money = []
+for _ in range(n):
+    money.append(int(input()))
+
+start = max(money)
+end = sum(money)
+
+ans = 0
+while start <= end:
+    mid = (start + end) // 2
+
+    total = 0
+    cnt = 0
+    for x in money:
+        if total + x <= mid:
+            total += x
+        else:
+            cnt += 1
+            total = 0
+            total += x
+    if total:
+        cnt += 1
+
+    if cnt > m:
+        start = mid + 1
+    else:
+        end = mid - 1
+        ans = mid
+
+print(ans)
\ No newline at end of file
diff --git "a/xxubin04/DP/2502_\353\226\241 \353\250\271\353\212\224 \355\230\270\353\236\221\354\235\264.py" "b/xxubin04/DP/2502_\353\226\241 \353\250\271\353\212\224 \355\230\270\353\236\221\354\235\264.py"
new file mode 100644
index 0000000..b531878
--- /dev/null
+++ "b/xxubin04/DP/2502_\353\226\241 \353\250\271\353\212\224 \355\230\270\353\236\221\354\235\264.py"	
@@ -0,0 +1,15 @@
+input = open(0).readline
+
+days, tteok_num = map(int, input().split())
+
+for i in range(1, tteok_num):
+    for j in range(i, tteok_num):
+        a = i; b = j
+        for k in range(2, days):
+            temp = a + b
+            a = b
+            b = temp
+
+        if temp == tteok_num:
+            print(f"{i}\n{j}")
+            exit()
\ No newline at end of file
diff --git a/xxubin04/README.md b/xxubin04/README.md
index 6717074..d7af60b 100644
--- a/xxubin04/README.md
+++ b/xxubin04/README.md
@@ -31,4 +31,4 @@
 | 27차시 | 2024.02.08 |  수학  | <a href="https://www.acmicpc.net/problem/2885">[2885]초콜릿 식사</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/98 |
 | 28차시 | 2024.02.15 |  이진탐색  | <a href="https://www.acmicpc.net/problem/2805">[2805]나무 자르기</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/108 |
 | 29차시 | 2024.02.19 |  DP  | <a href="https://www.acmicpc.net/problem/2502">[2502]떡 먹는 호랑이</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/110 |
-| 30차시 | 2024.02.22 |  BFS  | <a href="https://www.acmicpc.net/problem/14562">[14562]태권왕</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/113 |
+| 30차시 | 2024.02.22 |  BFS  | <a href="https://www.acmicpc.net/problem/14562">[14562]태권왕</a>  | https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/113 |
\ No newline at end of file