From e9febbc362d65fa0cce451c3290b61927ff9481d Mon Sep 17 00:00:00 2001
From: oncsr <khj20006@naver.com>
Date: Sat, 8 Nov 2025 10:53:19 +0900
Subject: [PATCH] =?UTF-8?q?[20251108]=20BOJ=20/=20P5=20/=20=EB=82=98?=
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---
 ...00\355\214\214\354\235\264\354\226\264.md" | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 "khj20006/202511/08 BOJ P5 \353\202\230\353\212\224 \353\261\200\355\214\214\354\235\264\354\226\264.md"

diff --git "a/khj20006/202511/08 BOJ P5 \353\202\230\353\212\224 \353\261\200\355\214\214\354\235\264\354\226\264.md" "b/khj20006/202511/08 BOJ P5 \353\202\230\353\212\224 \353\261\200\355\214\214\354\235\264\354\226\264.md"
new file mode 100644
index 00000000..0f6cd4be
--- /dev/null
+++ "b/khj20006/202511/08 BOJ P5 \353\202\230\353\212\224 \353\261\200\355\214\214\354\235\264\354\226\264.md"	
@@ -0,0 +1,40 @@
+```cpp
+#include <bits/stdc++.h>
+using namespace std;
+
+int N, M, R;
+vector<vector<int>> v(100001);
+
+pair<int, int> f(int n, int p, int t) {
+    int d = t, c = 0, l = 0;
+    for(int i:v[n]) if(i != p) {
+        auto [dd, cc] = f(i, n, t);
+        d = min(d, dd+1);
+        c += cc;
+        l++;
+    }
+    if(!l) return {0,1};
+    if(d == t && n != R) c++, d = 0;
+    return {d,c};
+}
+
+int main() {
+    cin.tie(0)->sync_with_stdio(0);
+
+    cin>>N>>M>>R;
+    for(int i=1,a,b;i<N;i++) {
+        cin>>a>>b;
+        v[a].push_back(b);
+        v[b].push_back(a);
+    }
+
+    int s = 1, e = N, m = (s+e)>>1;
+    while(s<e) {
+        if(f(R, 0, m).second > M) s = m+1;
+        else e = m;
+        m = (s+e)>>1;
+    }
+    cout<<(m == N ? -1 : m);
+
+}
+```