From 884d1b4ee44dfac03cc58cad7f504a70503731c4 Mon Sep 17 00:00:00 2001
From: Baoshuo <i@baoshuo.ren>
Date: Mon, 6 Jun 2022 16:28:40 +0800
Subject: [PATCH] =?UTF-8?q?P4151=20[WC2011]=E6=9C=80=E5=A4=A7XOR=E5=92=8C?=
 =?UTF-8?q?=E8=B7=AF=E5=BE=84?=
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https://www.luogu.com.cn/record/77021578
---
 Luogu/P4151/P4151.cpp        | 69 ++++++++++++++++++++++++++++++++++++
 Luogu/P4151/data/P4151_1.in  |  3 ++
 Luogu/P4151/data/P4151_1.out |  3 ++
 3 files changed, 75 insertions(+)
 create mode 100644 Luogu/P4151/P4151.cpp
 create mode 100644 Luogu/P4151/data/P4151_1.in
 create mode 100644 Luogu/P4151/data/P4151_1.out

diff --git a/Luogu/P4151/P4151.cpp b/Luogu/P4151/P4151.cpp
new file mode 100644
index 00000000..236a23b7
--- /dev/null
+++ b/Luogu/P4151/P4151.cpp
@@ -0,0 +1,69 @@
+#include <iostream>
+#include <utility>
+#include <vector>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 50005;
+
+int n, m;
+bool vis[N];
+unsigned long long p[N], dep[N], ans;
+std::vector<std::pair<int, unsigned long long>> g[N];
+
+inline void insert(unsigned long long x) {
+    for (int i = 60; ~i; i--) {
+        if (x & (1ull << i)) {
+            if (p[i]) {
+                x ^= p[i];
+            } else {
+                p[i] = x;
+                return;
+            }
+        }
+    }
+}
+
+void dfs(int u, unsigned long long sum) {
+    vis[u] = true;
+    dep[u] = sum;
+
+    for (auto e : g[u]) {
+        int v = e.first;
+        unsigned long long w = e.second;
+
+        if (vis[v]) insert(sum ^ dep[v] ^ w);
+        else dfs(v, sum ^ w);
+    }
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> m;
+
+    for (int i = 1; i <= m; i++) {
+        int s, t;
+        unsigned long long d;
+
+        cin >> s >> t >> d;
+
+        g[s].push_back(std::make_pair(t, d));
+        g[t].push_back(std::make_pair(s, d));
+    }
+
+    dfs(1, 0);
+
+    ans = dep[n];
+
+    for (int i = 60; ~i; i--) {
+        if ((ans ^ p[i]) > ans) ans ^= p[i];
+    }
+
+    cout << ans << endl;
+
+    return 0;
+}
diff --git a/Luogu/P4151/data/P4151_1.in b/Luogu/P4151/data/P4151_1.in
new file mode 100644
index 00000000..91d2b6e7
--- /dev/null
+++ b/Luogu/P4151/data/P4151_1.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:2a2b2226e1d06a73ded6334fa900ae550bb366758170dcf3ace9dcfb74c469cf
+size 10659
diff --git a/Luogu/P4151/data/P4151_1.out b/Luogu/P4151/data/P4151_1.out
new file mode 100644
index 00000000..5a77f7cb
--- /dev/null
+++ b/Luogu/P4151/data/P4151_1.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:d4f04901f6aa37f0ac9c0b96152b3734d7d799a3ac7b3b6c00bbeb569c723abd
+size 6