2024-07-19

tgyuuAn/README.md

@@ -68,4 +68,5 @@
 | 61차시 | 2024.06.20 |  크루스칼  | <a href="https://www.acmicpc.net/problem/1774">우주신과의 교감</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/212
 | 62차시 | 2024.07.01 |  DP  | <a href="https://www.acmicpc.net/problem/1949">우수 마을</a> | https://github.com/AlgoLeadMe/AlgoLeadMse-1/pull/214
 | 63차시 | 2024.07.08 |  BFS  | <a href="https://www.acmicpc.net/problem/3108">로고</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/216
+| 65차시 | 2024.07.19 |  최소 공통 조상  | <a href="https://www.acmicpc.net/problem/3584">가장 가까운 공통 조상</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/220
 ---

tgyuuAn/최소 공통 조상/가장 가까운 공통 조상.py

@@ -0,0 +1,39 @@
+import sys
+
+def input(): return sys.stdin.readline().rstrip()
+
+T = int(input())
+for _ in range(T):
+    N = int(input())
+    parent = [0 for _ in range(N+1)]
+
+    for _ in range(N-1):
+        A, B = map(int, input().split())
+        parent[B] = A
+
+    x, y = map(int, input().split())
+    x_depth = 0
+    now_node = x
+    while now_node != 0:
+        now_node = parent[now_node]
+        x_depth += 1
+
+    y_depth = 0
+    now_node = y
+    while now_node != 0:
+        now_node = parent[now_node]
+        y_depth += 1
+
+    while x_depth > y_depth:
+        x_depth -= 1
+        x = parent[x]
+
+    while y_depth > x_depth:
+        y_depth -= 1
+        y = parent[y]
+
+    while x != y:
+        x = parent[x]
+        y = parent[y]
+
+    print(x)