'commit'

TangDou/AcWing/DisjointSet/240_KZY.cpp

@@ -0,0 +1,49 @@
+#include <bits/stdc++.h>
+using namespace std;
+const int N = 150010;
+int p[N];
+int ans;
+int find(int x) {
+    if (p[x] != x) p[x] = find(p[x]);
+    return p[x];
+}
+void join(int x, int y) {
+    int f1 = find(x), f2 = find(y);
+    if (f1 != f2) p[f1] = f2;
+}
+int main() {
+    int n, m;
+    cin >> n >> m;
+    for (int i = 1; i <= 3 * n; i++) p[i] = i; // 并查集初始化
+
+    while (m--) {
+        int x, y, t;
+        cin >> t >> x >> y;
+        // 说出大于n编号的动物，肯定是假话
+        if (x > n || y > n) {
+            ans++;
+            continue;
+        }
+        if (t == 1) { // x和y同类
+            if (find(x + n) == find(y) || find(x + 2 * n) == find(y)) {
+                ans++;
+                continue;
+            }
+            join(x, y);
+            join(x + n, y + n);
+            join(x + 2 * n, y + 2 * n);
+        }
+        if (t == 2) { // x吃y
+                      // +n  天敌，+2n 食物
+            if (find(x) == find(y) || find(x + n) == find(y)) {
+                ans++;
+                continue;
+            }
+            join(x, y + n);
+            join(x + n, y + 2 * n);
+            join(x + 2 * n, y);
+        }
+    }
+    printf("%d\n", ans);
+    return 0;
+}