From 00408f112d18b7bdff4dafc003c2e82ef8e8e311 Mon Sep 17 00:00:00 2001
From: SUMIN <ssumim02@gmail.com>
Date: Sat, 11 Apr 2026 11:55:27 +0900
Subject: [PATCH] =?UTF-8?q?Upload=20files=20to=20"=EB=B0=B1=EC=A4=80"?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 백준/1967.py | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 백준/1991.py | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 백준/2023.py | 36 ++++++++++++++++++++++++++++++++++++
 백준/2096.py | 24 ++++++++++++++++++++++++
 백준/2156.py | 22 ++++++++++++++++++++++
 5 files changed, 180 insertions(+)
 create mode 100644 백준/1967.py
 create mode 100644 백준/1991.py
 create mode 100644 백준/2023.py
 create mode 100644 백준/2096.py
 create mode 100644 백준/2156.py

diff --git a/백준/1967.py b/백준/1967.py
new file mode 100644
index 0000000..53af7d6
--- /dev/null
+++ b/백준/1967.py
@@ -0,0 +1,46 @@
+import sys
+from collections import deque
+from collections import defaultdict
+
+sys.setrecursionlimit(10**6)
+
+input = sys.stdin.readline
+
+graph = defaultdict(list)
+
+n = int(input())
+for _ in range(n-1):
+    parent, son, weight = map(int, input().split())
+    graph[parent].append((son, weight))
+    graph[son].append((parent, weight))
+
+
+dist = [-1 for _ in range(10001)]
+
+def BFS(start):
+    q = deque([start])
+    visited = set([start])
+    while q:
+        now = q.popleft()
+        for next, weight in graph[now]:
+            if next not in visited:
+                q.append(next)
+                visited.add(next)
+                dist[next] = dist[now] + weight
+
+dist[1] = 0
+BFS(1)
+
+value = -1
+index = 0
+for i in range(10001):
+    if(dist[i]>value):
+        value = dist[i]
+        index = i
+
+dist = [-1 for _ in range(10001)]
+dist[index] = 0
+
+BFS(index)
+
+print(max(dist))
\ No newline at end of file
diff --git a/백준/1991.py b/백준/1991.py
new file mode 100644
index 0000000..c2dc411
--- /dev/null
+++ b/백준/1991.py
@@ -0,0 +1,52 @@
+import sys
+import math
+from collections import deque
+from collections import defaultdict
+
+input=sys.stdin.readline
+
+n = int(input())
+tree = defaultdict(list)
+
+for i in range(n):
+    node, left, right = map(str, input().split())
+    tree[node].append(left)
+    tree[node].append(right)
+
+def preorder(i):
+    if(tree[i] == '.'):
+        return
+    elif(tree[i]):
+        print(i, end='')
+        preorder(tree[i][0])
+        preorder(tree[i][1])
+    else:
+        return
+
+def midorder(i):
+    if(tree[i] == '.'):
+        return
+    elif(tree[i]):
+        midorder(tree[i][0])
+        print(i, end='')
+        midorder(tree[i][1])
+    else:
+        return
+
+
+
+def lastorder(i):
+    if(tree[i] == '.'):
+        return
+    elif(tree[i]):
+        lastorder(tree[i][0])
+        lastorder(tree[i][1])
+        print(i, end='')
+    else:
+        return
+
+preorder('A')
+print()
+midorder('A')
+print()
+lastorder('A')
diff --git a/백준/2023.py b/백준/2023.py
new file mode 100644
index 0000000..d399e5c
--- /dev/null
+++ b/백준/2023.py
@@ -0,0 +1,36 @@
+import sys
+sys.setrecursionlimit(10**6)
+
+input = sys.stdin.readline
+
+N = int(input())
+arr= [0] * (10**N)
+arr[0] = 1
+arr[1] = 1
+result = []
+
+def is_prime(n):
+    
+
+def prime(n):
+    p=2
+    while(p*p<n):
+        if 
+
+def dfs(u, digit):
+    if(u >= (10**N) or digit>=N) :
+        if(arr[u]==0):
+            result.append(u)
+        return
+    if(arr[u]==1) : return
+    else :
+        for i in range(1, 10):
+            dfs(u+(i*(10**digit)), digit+1)
+
+for i in range(1, 10):
+    dfs(i, 1)
+
+sorarr=sorted(set(result))
+
+for i in sorarr:
+    print(i)
\ No newline at end of file
diff --git a/백준/2096.py b/백준/2096.py
new file mode 100644
index 0000000..b52ff7f
--- /dev/null
+++ b/백준/2096.py
@@ -0,0 +1,24 @@
+import sys
+
+input = sys.stdin.readline
+
+N = int(input().rstrip())
+
+dp = [0]*7
+for i in range(1, N+1):
+    a, b, c = map(int, input().split())
+    j, k, l = dp[0], dp[1], dp[2]
+    m, n, o = dp[3], dp[4], dp[5]
+    dp[0] = max(j, k) + a
+    dp[1] = max(j, k, l) + b
+    dp[2] = max(k, l) + c
+
+    dp[3] = min(m, n) + a
+    dp[4] = min(m, n, o) + b
+    dp[5] = min(n, o) + c
+
+
+print(max(dp[0], dp[1], dp[2]), end=' ')
+print(min(dp[3], dp[4], dp[5]))
+
+
diff --git a/백준/2156.py b/백준/2156.py
new file mode 100644
index 0000000..3573d6a
--- /dev/null
+++ b/백준/2156.py
@@ -0,0 +1,22 @@
+import sys
+
+input = sys.stdin.readline
+
+n = int(input())
+
+arr = []
+
+for i in range(n):
+    arr.append(int(input()))
+
+li_sum = [0 for _ in range(n)]
+
+if(n>=3):
+    li_sum[0] = arr[0]
+    li_sum[1] = arr[0]+arr[1]
+    li_sum[2] = max(arr[0]+arr[1] , arr[1]+arr[2], arr[0]+arr[2])
+    for i in range(3, n):
+        li_sum[i] = max(li_sum[i-2]+arr[i], li_sum[i-1], li_sum[i-3]+arr[i-1]+arr[i])
+    print(li_sum[n-1])
+else:
+    print(sum(arr))
\ No newline at end of file