Submission #1036986

#	Time	Username	Problem	Language	Result	Execution time	Memory
1036986		aaaaaarroz	Sky Walking (IOI19_walk)	C++17	24 / 100	4035 ms	631436 KiB

walk

#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "walk.h"
 
struct BRIDGE {
    int l, r, y;
};
struct BUILDING {
    int x, h;
};
 
namespace TEST4 {
    struct SEGTREE {
        int n;
        VI tree;
        VI lazy;
        SEGTREE(int sz) {
            n = 1;
            while (n < sz) n *= 2;
            lazy = tree = VI(2*n, -1);
        }
        void push(int N) {
            if (lazy[N] == -1) return;
            tree[N] = lazy[N];
            if (N <= n-2) {
                lazy[2*N+1] = lazy[N];
                lazy[2*N+2] = lazy[N];
            }
            lazy[N] = -1;
        }
        int get(int N, int L, int R, int l, int r) {
            push(N);
            if (l <= L && R <= r) return tree[N];
            if (R < l || L > r) return -1;
            int M = (L + R) / 2;
            return max(get(2*N+1, L, M, l, r), get(2*N+2, M+1, R, l, r));
        }
        void upd(int N, int L, int R, int l, int r, int s) {
            push(N);
            if (R < l || L > r) return;
            if (l <= L && R <= r) {
                lazy[N] = s;
                push(N);
                return;
            }
            int M = (L + R) / 2;
            upd(2*N+1, L, M, l, r, s);
            upd(2*N+2, M+1, R, l, r, s);
            tree[N] = max(tree[2*N+1], tree[2*N+2]);
        }
        int get(int l, int r) {
            return get(0, 0, n-1, l, r);
        }
        int get(int i) {
            return get(0, 0, n-1, i, i);
        }
        void upd(int l, int r, int s) {
            upd(0, 0, n-1, l, r, s);
        }
    };
};
 
ll min_distance(VI X, VI H, VI L, VI R, VI Y, int S, int T) {
    vector<BUILDING> buildings(X.size());
    rep(i, X.size()) buildings[i] = {X[i], H[i]};
    vector<BRIDGE> bridges(L.size());
    rep(i, L.size()) bridges[i] = {L[i], R[i], Y[i]};
    map<PII, int> ind;
    VPI point;
    VVPI gp;
    auto addvertex = [&](int x, int y) {
        if (ind.count({x, y})) return;
        ind[{x, y}] = gp.size();
        point.pb({x, y});
        gp.pb(VPI());
    };
    if (S == 0 && T == X.size()-1 && false) {
        /*TEST 4 */
        addvertex(0, 0);
        addvertex(X.size()-1, 0);
        /* vertical */
        sort(all(bridges), [](const BRIDGE& a, const BRIDGE& b){return a.y < b.y;});
        TEST4::SEGTREE seg(X.size());
        seg.upd(0, 0, 0);
        seg.upd(X.size()-1, X.size()-1, 0);
        for (auto&[l, r, y] : bridges) {
            addvertex(l, y);
            addvertex(r, y);
            for (int x : {l, r}) {
                int vy = seg.get(x);
                if (vy == -1) continue;
                addvertex(x, vy);
                int u = ind[{x, y}];
                int v = ind[{x, vy}];
                int w = y - vy;
                gp[u].pb({v, w});
                gp[v].pb({u, w});
            }
            seg.upd(l, r, y);
        }
        /* horizontal */
        VPI pts = point;
        sort(all(pts), [](const PII& a, const PII& b){return mkp(a.ss, a.ff) < mkp(b.ss, b.ff);});
        rep(i, pts.size()-1) {
            if (pts[i].ss == 0) continue;
            if (pts[i].ss != pts[i+1].ss) continue;
            int u = ind[pts[i]];
            int v = ind[pts[i+1]];
            int w = X[pts[i+1].ff] - X[pts[i].ff];
            gp[u].pb({v, w});
            gp[v].pb({u, w});
        }
    } else {
        /* TEST 1, 2 */
        addvertex(X[S], 0);
        addvertex(X[T], 0);
        for (auto&[a, b, c] : bridges) a = X[a], b = X[b]; 
        sort(all(buildings), [](const BUILDING& a, const BUILDING& b){return a.h > b.h;});
        sort(all(bridges), [](const BRIDGE& a, const BRIDGE& b){return a.y > b.y;});
        /* horizontal */
        set<int> st;
        for (int j = 0, i = 0; i < bridges.size(); i++) {
            auto&[l, r, y] = bridges[i];
            while (j < buildings.size() && buildings[j].h >= y) st.insert(buildings[j++].x);
            VI xs;
            for (auto it = st.lower_bound(l); it != st.end() && *it <= r; it++) xs.pb(*it);
            for (int x : xs) addvertex(x, y);
            rep(i, xs.size()-1) {
                int u = ind[{xs[i], y}];
                int v = ind[{xs[i+1], y}];
                int w = xs[i+1]-xs[i];
                gp[u].pb({v, w});
                gp[v].pb({u, w});
            }
        }
        /* vertical */
        VPI pts = point;
        sort(all(pts));
        rep(i, pts.size()-1) {
            if (pts[i].ff != pts[i+1].ff) continue;
            int u = ind[pts[i]];
            int v = ind[pts[i+1]];
            int w = pts[i+1].ss - pts[i].ss;
            gp[u].pb({v, w});
            gp[v].pb({u, w});
        }
    }
    int n = gp.size();
    priority_queue<PLL> pq;
    VL dist(n, 1e18);
    VI vis(n);
    pq.push({0, 0});
    dist[0] = 0;
    while (pq.size()) {
        int u = pq.top().ss;
        pq.pop();
        if (vis[u]) continue;
        vis[u] = true;
        for (auto[v, w] : gp[u]) {
            if (dist[u] + w < dist[v]) {
                dist[v] = dist[u] + w;
                pq.push({-dist[v], v});
            }
        }
    }
    if (dist[1] == 1e18) return -1;
	return dist[1];
}

Compilation message (stderr)

walk.cpp: In function 'll min_distance(VI, VI, VI, VI, VI, int, int)':
walk.cpp:105:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  105 |     if (S == 0 && T == X.size()-1 && false) {
      |                   ~~^~~~~~~~~~~~~
walk.cpp:150:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<BRIDGE>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  150 |         for (int j = 0, i = 0; i < bridges.size(); i++) {
      |                                ~~^~~~~~~~~~~~~~~~
walk.cpp:152:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<BUILDING>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  152 |             while (j < buildings.size() && buildings[j].h >= y) st.insert(buildings[j++].x);
      |                    ~~^~~~~~~~~~~~~~~~~~

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