제출 #418178

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
418178		usachevd0	Sky Walking (IOI19_walk)	C++17	15 / 100	178 ms	18464 KiB

walk

#include <bits/stdc++.h>
#ifndef LOCAL
    #include "walk.h"
#endif

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define Time (clock() * 1.0 / CLOCKS_PER_SEC)
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
template<typename T1, typename T2> bool chkmin(T1& x, T2 y) {
    return y < x ? (x = y, true) : false;
}
template<typename T1, typename T2> bool chkmax(T1& x, T2 y) {
    return y > x ? (x = y, true) : false;
}
void debug_out() {
    cerr << endl;
}
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) {
    cerr << ' ' << A;
    debug_out(B...);
}
template<typename T> void mdebug_out(T* a, int n) {
    for (int i = 0; i < n; ++i)
        cerr << a[i] << ' ';
    cerr << endl;
}
#ifdef LOCAL
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
    #define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
    #define debug(...) 1337
    #define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T>& v) {
    for (auto& x : v)
        stream << x << ' ';
    return stream;
}
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) {
    return stream << p.first << ' ' << p.second;
}

const ll INF64 = 1e18;
#ifdef LOCAL
    const int maxN = 35;
#else
    const int maxN = 100005;
#endif
int n, m;
vector<int> bg[maxN], en[maxN];
ll V[maxN];

namespace sgt {
    const int logN = 17;
    const int N = 1 << logN;
    int mx[2 * N];
    
    void build(vector<int>& H) {
        for (int i = 0; i < n; ++i)
            mx[i + N] = H[i];
        for (int i = N - 1; i >= 1; --i)
            mx[i] = max(mx[i << 1], mx[i << 1 | 1]);
    }
    int rmxq(int l, int r) {
        int ans = -1e9;
        for (l += N, r += N; l <= r; l >>= 1, r >>= 1) {
            if (l & 1)  chkmax(ans, mx[l++]);
            if (~r & 1) chkmax(ans, mx[r--]);
        }
        return ans;
    }
}

namespace dsu {
    int q[maxN];
    
    void init() {
        memset(q, 255, sizeof q);
    }
    int gt(int x) {
        return q[x] < 0 ? x : q[x] = gt(q[x]);
    }
    bool join(int x, int y) { // y is the parent of x
        x = gt(x), y = gt(y);
        if (x == y) return false;
        //if (-q[x] > -q[y]) swap(x, y);
        q[y] += q[x];
        q[x] = y;
        return true;
    }
}

ll min_distance(vector<int> X, vector<int> H, vector<int> L, vector<int> R, vector<int> Y, int SI, int TI) {
    n = X.size(), m = L.size();
    assert(SI == 0 && TI == n - 1);
    
    for (int j = 0; j < m; ++j) {
        int l = L[j], r = R[j];
        bg[l].push_back(j);
        en[r].push_back(j);
    }
    
    
    
    dsu::init();
    fill(V, V + m, INF64);
    auto gv = [&](int j) -> ll {
        return V[j];
        int r = dsu::gt(j);
        return V[r] + Y[r] - Y[j];
    };
    
    set<pii> a;
    for (int j : bg[0]) {
        int y = Y[j];
        a.insert({y, j});
        V[j] = y;
    }
    
    sgt::build(H);
    
    set<pii> needUp;
    for (int i = 1; i < n; ++i) {
        if (a.empty()) return -1;
        
        // while (!needUp.empty()) {
        //     int y = -needUp.begin()->fi;
        //     if (y > H[i]) break;
        //     int j = needUp.begin()->se;
        //     if (!a.count({Y[j], j})) continue;
        //     needUp.erase(needUp.begin());
        //     auto it = a.upper_bound({Y[j], j});
        //     if (it != a.end() && it->fi <= H[i]) {
        //         ll fv = it->fi - Y[j] + gv(it->se);
        //         if (fv <= V[j]) {
        //             V[j] = fv;
        //             dsu::join(j, it->se);
        //         }
        //     }
        // }
        
        for (int j : bg[i]) {
            V[j] = +INF64;
            auto it = a.lower_bound({Y[j], -1});
            if (it != a.begin()) {
                auto pit = prev(it);
                chkmin(V[j], Y[j] - pit->fi + gv(pit->se));
            }
            if (it != a.end() && it->fi <= H[i]) {
                ll fv = it->fi - Y[j] + gv(it->se);
                if (fv <= V[j]) {
                    V[j] = fv;
                    // dsu::join(j, it->se);
                }
            }
            else if (it != a.end()) {
                int j1 = it->se;
                int r = min(R[j], R[j1]);
                if (sgt::rmxq(i, r) >= Y[j1]) {
                    ll fv = it->fi - Y[j] + gv(it->se);
                    if (fv <= V[j]) {
                        V[j] = fv;
                        // dsu::join(j, it->se);
                    }
                }
                // needUp.insert({it->fi, j});
            }
            a.insert({Y[j], j});
        }
        if (i == n - 1) break;
        for (int j : en[i]) {
            int y = Y[j];
            a.erase({y, j});
        }
        
        // debug(i);
        // for (auto el : a) cerr << el << ' ' << gv(el.se) << "  "; cerr << endl;
    }
    ll ans = INF64;
    for (auto& [y, j] : a) {
        chkmin(ans, X[n - 1] - X[0] + y + gv(j));
    }
    return ans;
}


#ifdef LOCAL

int32_t main() {
#ifdef LOCAL
    freopen("in", "r", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    
        int n, m;
    assert(2 == scanf("%d%d", &n, &m));
    vector<int> x(n), h(n);
    for (int i = 0; i < n; i++)
        assert(2 == scanf("%d%d", &x[i], &h[i]));
    vector<int> l(m), r(m), y(m);
    for (int i = 0; i < m; i++)
        assert(3 == scanf("%d%d%d", &l[i], &r[i], &y[i]));
    int s, g;
    assert(2 == scanf("%d%d", &s, &g));
    fclose(stdin);

    long long result = min_distance(x, h, l, r, y, s, g);

    printf("%lld\n", result);
    fclose(stdout);
    
    return 0;
}

#endif

• Subtask 1: 0 / 10
• Subtask 2: 0 / 14
• Subtask 3: 15 / 15
• Subtask 4: 0 / 18
• Subtask 5: 0 / 43