1 条题解

  • 0
    @ 2026-11-2 13:11:10

    遗产传送门(Legacy) 题解

    思路分析

    按题目要求使用对应数据结构与算法模拟/递推求解,注意数据范围边界与时间复杂度。

    参考代码

    #include <iostream>
    #include <vector>
    #include <queue>
    using namespace std;
    
    const long long INF = (1LL << 60);
    int n, q, s;
    int totNodes;
    vector<vector<pair<int, long long>>> adj;
    vector<int> outId, inId;
    
    void build(int u, int l, int r) {
        outId[u] = ++totNodes;
        inId[u] = ++totNodes;
        if (l == r) {
            adj[outId[u]].push_back({l, 0});
            adj[l].push_back({inId[u], 0});
            return;
        }
        int mid = (l + r) >> 1;
        build(u << 1, l, mid);
        build(u << 1 | 1, mid + 1, r);
        adj[outId[u]].push_back({outId[u << 1], 0});
        adj[outId[u]].push_back({outId[u << 1 | 1], 0});
        adj[inId[u << 1]].push_back({inId[u], 0});
        adj[inId[u << 1 | 1]].push_back({inId[u], 0});
    }
    
    void addOut(int u, int l, int r, int ql, int qr, int from, long long w) {
        if (ql <= l && r <= qr) {
            adj[from].push_back({outId[u], w});
            return;
        }
        int mid = (l + r) >> 1;
        if (ql <= mid) addOut(u << 1, l, mid, ql, qr, from, w);
        if (qr > mid) addOut(u << 1 | 1, mid + 1, r, ql, qr, from, w);
    }
    
    void addIn(int u, int l, int r, int ql, int qr, int to, long long w) {
        if (ql <= l && r <= qr) {
            adj[inId[u]].push_back({to, w});
            return;
        }
        int mid = (l + r) >> 1;
        if (ql <= mid) addIn(u << 1, l, mid, ql, qr, to, w);
        if (qr > mid) addIn(u << 1 | 1, mid + 1, r, ql, qr, to, w);
    }
    
    int main() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
        if (!(cin >> n >> q >> s)) return 0;
        totNodes = n;
        adj = vector<vector<pair<int, long long>>>(9 * n + 20);
        outId = vector<int>(4 * n + 10, 0);
        inId = vector<int>(4 * n + 10, 0);
        build(1, 1, n);
        for (int i = 0; i < q; ++i) {
            int t;
            cin >> t;
            if (t == 1) {
                int v, u;
                long long w;
                cin >> v >> u >> w;
                adj[v].push_back({u, w});
            } else if (t == 2) {
                int v, l, r;
                long long w;
                cin >> v >> l >> r >> w;
                addOut(1, 1, n, l, r, v, w);
            } else {
                int v, l, r;
                long long w;
                cin >> v >> l >> r >> w;
                addIn(1, 1, n, l, r, v, w);
            }
        }
        vector<long long> dist(totNodes + 1, INF);
        priority_queue<pair<long long, int>, vector<pair<long long, int>>, greater<pair<long long, int>>> pq;
        dist[s] = 0;
        pq.push({0, s});
        while (!pq.empty()) {
            auto [d, u] = pq.top();
            pq.pop();
            if (d > dist[u]) continue;
            for (auto [v, w] : adj[u]) {
                if (dist[u] + w < dist[v]) {
                    dist[v] = dist[u] + w;
                    pq.push({dist[v], v});
                }
            }
        }
        for (int i = 1; i <= n; ++i) {
            long long ans = (dist[i] == INF ? -1 : dist[i]);
            cout << ans << (i == n ? "\n" : " ");
        }
        return 0;
    }
    
    • 1

    信息

    ID
    8648
    时间
    2000ms
    内存
    256MiB
    难度
    (无)
    标签
    递交数
    0
    已通过
    0
    上传者