'commit'

TangDou/AcWing/ChaFenYueShu/1169_hh_tt.cpp

@@ -0,0 +1,65 @@
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long LL;
+const int N = 100010, M = 300010;
+int n, m;
+int h[N], e[M], w[M], ne[M], idx;
+int q[N], cnt[N];
+LL dist[N];
+bool st[N];
+void add(int a, int b, int c) {
+    e[idx] = b, w[idx] = c, ne[idx] = h[a], h[a] = idx++;
+}
+bool spfa() {
+    int hh = 0, tt = -1;
+    for (int i = 1; i <= n; i++) {
+        q[++tt] = i;
+        st[i] = true;
+        dist[i] = 1;
+    }
+
+    while (hh <= tt) {
+        int u = q[hh++];
+        st[u] = false;
+
+        for (int i = h[u]; ~i; i = ne[i]) {
+            int v = e[i];
+            if (dist[v] < dist[u] + w[i]) {
+                dist[v] = dist[u] + w[i];
+                cnt[v] = cnt[u] + 1;
+                if (cnt[v] >= n) return true;
+                if (!st[v]) {
+                    q[++tt] = v;
+                    st[v] = true;
+                }
+            }
+        }
+    }
+    return false;
+}
+int main() {
+    // 最小值最长路,i->j,dj>=di+c
+    memset(h, -1, sizeof h);
+
+    cin >> n >> m;
+
+    while (m--) {
+        int x, a, b;
+        cin >> x >> a >> b;
+        if (x == 1) add(a, b, 0), add(b, a, 0); // A=B,A>=B,B>=A
+        if (x == 2) add(a, b, 1);               // A<B,B-1>=A
+        if (x == 3) add(b, a, 0);               // A>=B,B->A
+        if (x == 4) add(b, a, 1);               // A>B,A>=B+1,B->A
+        if (x == 5) add(a, b, 0);               // A<=B,B>=A,A->B
+    }
+
+    if (spfa())
+        puts("-1");
+    else {
+        LL res = 0;
+        for (int i = 1; i <= n; i++) res += dist[i];
+        printf("%lld\n", res);
+    }
+
+    return 0;
+}