feat: 添加两个图的割点算法实现

实现基于Tarjan算法的割点检测功能，分别用于解决P3388和P8436问题

src/10/2/P3388.cpp

@@ -0,0 +1,72 @@
+#include <algorithm>
+#include <iostream>
+#include <vector>
+
+const int MAXN = 2e4 + 5; 
+
+int n, m;
+std::vector<int> adj[MAXN];
+
+int dfn[MAXN], low[MAXN], ts;
+bool is_cut[MAXN]; 
+std::vector<int> cut_points; 
+
+void tarjan(int u, int parent) {
+    dfn[u] = low[u] = ++ts;
+    int child_count = 0; 
+    for (int v : adj[u]) {
+        if (v == parent) {
+            continue;
+        }
+        if (!dfn[v]) {
+            child_count++;
+            tarjan(v, u);
+            low[u] = std::min(low[u], low[v]);
+            if (parent != 0 && low[v] >= dfn[u]) {
+                is_cut[u] = true;
+            }
+        } else {
+            low[u] = std::min(low[u], dfn[v]);
+        }
+    }
+    if (parent == 0 && child_count > 1) {
+        is_cut[u] = true;
+    }
+}
+
+int main() {
+    std::ios_base::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    std::cin >> n >> m;
+    for (int i = 0; i < m; ++i) {
+        int u, v;
+        std::cin >> u >> v;
+        if (u == v) continue;
+        adj[u].push_back(v);
+        adj[v].push_back(u);
+    }
+    for (int i = 1; i <= n; ++i) {
+        if (!dfn[i]) {
+            tarjan(i, 0);
+        }
+    }
+    int count = 0;
+    for (int i = 1; i <= n; ++i) {
+        if (is_cut[i]) {
+            count++;
+        }
+    }
+    std::cout << count << "\n";
+    bool first = true;
+    for (int i = 1; i <= n; ++i) {
+        if (is_cut[i]) {
+            if (!first) {
+                std::cout << " ";
+            }
+            std::cout << i;
+            first = false;
+        }
+    }
+    std::cout << "\n";
+}

src/10/2/P8436.cpp

@@ -0,0 +1,72 @@
+#include <algorithm>
+#include <iostream>
+#include <vector>
+
+const int MAXN = 2e4 + 5; 
+
+int n, m;
+std::vector<int> adj[MAXN];
+
+int dfn[MAXN], low[MAXN], ts;
+bool is_cut[MAXN]; 
+std::vector<int> cut_points; 
+
+void tarjan(int u, int parent) {
+    dfn[u] = low[u] = ++ts;
+    int child_count = 0; 
+    for (int v : adj[u]) {
+        if (v == parent) {
+            continue;
+        }
+        if (!dfn[v]) {
+            child_count++;
+            tarjan(v, u);
+            low[u] = std::min(low[u], low[v]);
+            if (parent != 0 && low[v] >= dfn[u]) {
+                is_cut[u] = true;
+            }
+        } else {
+            low[u] = std::min(low[u], dfn[v]);
+        }
+    }
+    if (parent == 0 && child_count > 1) {
+        is_cut[u] = true;
+    }
+}
+
+int main() {
+    std::ios_base::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    std::cin >> n >> m;
+    for (int i = 0; i < m; ++i) {
+        int u, v;
+        std::cin >> u >> v;
+        if (u == v) continue;
+        adj[u].push_back(v);
+        adj[v].push_back(u);
+    }
+    for (int i = 1; i <= n; ++i) {
+        if (!dfn[i]) {
+            tarjan(i, 0);
+        }
+    }
+    int count = 0;
+    for (int i = 1; i <= n; ++i) {
+        if (is_cut[i]) {
+            count++;
+        }
+    }
+    std::cout << count << "\n";
+    bool first = true;
+    for (int i = 1; i <= n; ++i) {
+        if (is_cut[i]) {
+            if (!first) {
+                std::cout << " ";
+            }
+            std::cout << i;
+            first = false;
+        }
+    }
+    std::cout << "\n";
+}//TODO REBUILD