Codeforces Round #588 (Div. 1) C. Konrad and Company Evaluation

直接建反边暴力 复杂度分析见https://blog.csdn.net/Izumi_Hanako/article/details/101267502

#include
using namespace std;
typedef long long ll;
const int MAXN = 100005;
ll out[MAXN], in[MAXN];
vector<int> G[MAXN];
int main() {
        int n, m;
        scanf("%d %d", &n, &m);
        for (int i = 1; i <= m; i++) {
                int u, v;
                scanf("%d %d", &u, &v);
                if (u < v) {
                        swap(u, v);
                }
                out[u]++, in[v]++;
                G[v].push_back(u);
        }
        ll ans = 0;
        for (int i = 1; i <= n; i++) {
                ans += out[i] * in[i];
        }
        cout << ans << endl;
        int Q;
        scanf("%d", &Q);
        while (Q--) {
                int x;
                scanf("%d", &x);
                ans -= out[x] * in[x];
                out[x] += G[x].size(), in[x] = 0;
                for (int v : G[x]) {
                        ans -= out[v] * in[v];
                        out[v]--, in[v]++;
                        ans += out[v] * in[v];
                        G[v].push_back(x);
                }
                G[x].clear();
                cout << ans << endl;
        }
        return 0;
}

 

转载于:https://www.cnblogs.com/Aragaki/p/11593652.html