P1983 车站分级

R41303290

problem/P1983/P1983.cpp

@@ -0,0 +1,47 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int  n, m, k, ans, l, a[1005], d[1005], c[1005][1005], f[1005];
+bool v[1005][1005];
+
+int dfs(int x) {
+    if (f[x]) {
+        return f[x];
+    }
+    for (int i = 1; i <= c[x][0]; i++) {
+        f[x] = max(f[x], dfs(c[x][i]));
+    }
+    return ++f[x];
+}
+
+int main() {
+    cin >> n >> m;
+    for (int i = 1; i <= m; i++) {
+        cin >> a[0];
+        for (int j = 1; j <= a[0]; j++) {
+            cin >> a[j];
+        }
+        l = 1;
+        for (int j = a[1]; j < a[a[0]]; j++) {
+            if (a[l] == j) {
+                l++;
+            }
+            else {
+                for (int k = 1; k <= a[0]; k++) {
+                    if (!v[a[k]][j]) {
+                        int t = a[k];
+                        c[t][0]++;
+                        c[t][c[t][0]] = j;
+                        v[t][j]       = 1;
+                    }
+                }
+            }
+        }
+    }
+    for (int i = 1; i <= n; i++) {
+        ans = max(ans, dfs(i));
+    }
+    cout << ans << endl;
+    return 0;
+}