Submission #761887

# Submission time Handle Problem Language Result Execution time Memory
761887 2023-06-20T10:59:22 Z MinaRagy06 Sky Walking (IOI19_walk) C++17
Compilation error
0 ms 0 KB
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define SZ(x) (int)x.size()

struct bheap {
    vector<int> heap, mp;
    vector<ll> val;
    bheap() {}
    bheap(int n) {
        val.assign(n, 1e9);
        mp.assign(n, -1);
    }
    void sink(int pos) {
        while ((pos << 1) + 1 < SZ(heap)) {
            int l = (pos << 1) + 1, r = (pos << 1) + 2;
            int smallest = l;
            if (r < SZ(heap) && val[heap[r]] < val[heap[l]]) smallest = r;
            if (val[heap[smallest]] < val[heap[pos]]){
                mp[heap[smallest]] = pos;
                mp[heap[pos]] = smallest;
                swap(heap[pos], heap[smallest]);
            } else {
                break;
            }
            pos = smallest;
        }
    }
    bool swim(int pos) {
        int p = (pos - 1) >> 1;
        if (!(pos && val[heap[p]] > val[heap[pos]])) return 0;
        while (pos && val[heap[p]] > val[heap[pos]]) {
            mp[heap[p]] = pos;
            mp[heap[pos]] = p;
            swap(heap[p], heap[pos]);
            pos = p;
            p = (pos - 1) >> 1;
        }
        return 1;
    }
    void push(int key, ll value) {
        int pos = SZ(heap);
        heap.push_back(key);
        mp[key] = pos;
        val[key] = value;
        swim(pos);
    }
    int pop() {
        int n = SZ(heap), ret = heap[0];
        mp[heap[0]] = n - 1;
        mp[heap[n - 1]] = 0;
        swap(heap[0], heap[n-1]);
        heap.pop_back();
        sink(0);
        return ret;
    }
    void update(int key, ll value) {
        int pos = mp[key];
        val[key] = value;
        if (!swim(pos)) {
            sink(pos);
        }
    }
    int top() {
        return heap[0];
    }
    bool empty() {
        return heap.empty();
    }
};
vector<int> intersect[100'005];
vector<int> adj[2'000'005];
vector<ll> dist[100'005];
vector<int> idx[100'005], mp[100'005];
pair<int, int> rev[2'000'005];
int sparse[17][200'005];
const ll INF = 1e18;
ll min_distance(vector<int> x, vector<int> h, vector<int> l, vector<int> r, vector<int> y, int s, int g) {
    l.push_back(0), r.push_back(0), y.push_back(0);
    vector<array<int, 3>> sorted(SZ(y));
    idx[s].push_back(0), dist[s].push_back(INF);
    for (int i = 0; i < SZ(y); i++) {
        sorted[i] = {l[i], r[i], y[i]};
    }
    sort(sorted.begin(), sorted.end(), [&](array<int, 3> _a, array<int, 3> _b) {return _a[2] < _b[2];});
    for (int i = 0; i < SZ(y); i++) {
        l[i] = sorted[i][0], r[i] = sorted[i][1], y[i] = sorted[i][2];
    }
    int n = SZ(x), m = SZ(l) - 1;
    for (int i = 0; i < n; i++) {
        sparse[0][i] = h[i];
    }
    for (int j = 1; j < 17; j++) {
        for (int i = 0; i < n; i++) {
            sparse[j][i] = max(sparse[j - 1][i], sparse[j - 1][i + (1 << (j - 1))]);
        }
    }
    for (int i = 1; i <= m; i++) {
        int j = l[i];
        while (j <= r[i]) {
            if (y[i] <= h[j]) {
                intersect[i].push_back(j);
                j++;
                continue;
            }
            int mx = 0;
            for (int k = 16; k >= 0; k--) {
                if (y[i] > max(mx, sparse[k][j])) {
                    mx = max(mx, sparse[k][j]);
                    j += (1 << k);
                }
            }
            if (j <= r[i]) {
                intersect[i].push_back(j);
                j++;
            }
        }
        for (int k = 0; k < SZ(intersect[i]); k++) {
            dist[intersect[i][k]].push_back(INF);
            idx[intersect[i][k]].push_back(i);
        }
    }
    int cur = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < SZ(idx[i]); j++) {
            rev[cur] = {i, j};
            mp[i].push_back(cur++); 
        }
    }
    for (int i = 1; i <= m; i++) {
        for (int k = 0; k < SZ(intersect[i]); k++) {
            int ypos = lower_bound(idx[intersect[i][k]].begin(), idx[intersect[i][k]].end(), i) - idx[intersect[i][k]].begin();
            if (k + 1 < SZ(intersect[i])) {
                int y2pos = lower_bound(idx[intersect[i][k + 1]].begin(), idx[intersect[i][k + 1]].end(), i) - idx[intersect[i][k + 1]].begin();
                int u = mp[intersect[i][k]][ypos];
                int v = mp[intersect[i][k + 1]][y2pos];
                adj[u].push_back(v);
            }
            if (k - 1 >= 0) {
                int y2pos = lower_bound(idx[intersect[i][k - 1]].begin(), idx[intersect[i][k - 1]].end(), i) - idx[intersect[i][k - 1]].begin();
                int u = mp[intersect[i][k]][ypos];
                int v = mp[intersect[i][k - 1]][y2pos];
                adj[u].push_back(v);
            }
        }
    }
    bheap pq(cur);
    pq.push(mp[s][0], 0);
    dist[s][0] = 0;
    while (!pq.empty()) {
        int node = pq.pop();
        int i = rev[node].first;
        int j = rev[node].second;
        ll d = dist[i][j];
        j = y[idx[i][j]];
        if (node - 1 >= 0 && rev[node - 1].first == i) {
            auto [nxt, nxth] = rev[node - 1];
            ll newd = d + abs(j - y[idx[nxt][nxth]]);
            if (dist[nxt][nxth] == INF) {
                dist[nxt][nxth] = newd;
                pq.push(mp[nxt][nxth], newd);
            } else if (newd < dist[nxt][nxth]) {
                dist[nxt][nxth] = newd;
                pq.update(mp[nxt][nxth], newd);
            }
        }
        if (node + 1 < cur && rev[node + 1].first == i) {
            auto [nxt, nxth] = rev[node + 1];
            ll newd = d + abs(j - y[idx[nxt][nxth]]);
            if (dist[nxt][nxth] == INF) {
                dist[nxt][nxth] = newd;
                pq.push(mp[nxt][nxth], newd);
            } else if (newd < dist[nxt][nxth]) {
                dist[nxt][nxth] = newd;
                pq.update(mp[nxt][nxth], newd);
            }
        }
        for (auto nxtnode : adj[node]) {
            auto [nxt, nxth] = rev[nxtnode];
            ll newd = d + abs(x[nxt] - x[i]) + abs(j - y[idx[nxt][nxth]]);
            if (dist[nxt][nxth] == INF) {
                dist[nxt][nxth] = newd;
                pq.push(mp[nxt][nxth], newd);
            } else if (newd < dist[nxt][nxth]) {
                dist[nxt][nxth] = newd;
                pq.update(mp[nxt][nxth], newd);
            }
        }
    }
    ll ans = INF;
    for (int i = 0; i < SZ(dist[g]); i++) {
        ans = min(ans, dist[g][i] + y[idx[g][i]]);
    }
    if (ans >= INF) return -1;
    return ans;
}
int main() {
    ios_base::sync_with_stdio(0), cin.tie(0);
    int N, M;
    cin >> N >> M;
    vector<int> X(N), H(N);
    for (int i = 0; i < N; i++) {
        cin >> X[i] >> H[i];
    }
    vector<int> L(M), R(M), Y(M);
    for (int i = 0; i < M; i++) {
        cin >> L[i] >> R[i] >> Y[i];
    }
    int S, G;
    cin >> S >> G;
    cout << min_distance(X, H, L, R, Y, S, G) << '\n';
    return 0;
}

Compilation message

/usr/bin/ld: /tmp/ccqxCJdA.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cc4fV4tB.o:walk.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status