oj.uz

Submission #1013336

# Submission time Handle Problem Language Result Execution time Memory
1013336 2024-07-03T12:23:57 Z boris_mihov Sky Walking (IOI19_walk) C++17
10 / 100
 4000 ms 194380 KB 
#include "walk.h"
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <vector>
#include <queue>
#include <stack>
#include <map>
 
typedef long long llong;
const int MAXN = 100000 + 10;
const int INTERSECTIONS = 10 + 5;
const llong INF = 1e18;
const int INTINF = 1e9;
const int MAXLOG = 17;
 
namespace
{
    int cnt;
    int n, m;
    int s, t;
    int h[MAXN];
    int x[MAXN];
    int left[MAXN];
    int right[MAXN];
    int y[MAXN];
    std::map <int,int> map[MAXN];
    bool vis[MAXN * INTERSECTIONS];
    llong dist[MAXN * INTERSECTIONS];
    std::vector <std::pair <int,int>> g[MAXN * INTERSECTIONS]; 
    int cntNodes;
}
 
struct Sparse
{
    int sparse[MAXLOG][MAXN];
    int getLOG[MAXN];
 
    void build(int a[])
    {
        for (int i = 1 ; i <= n ; ++i)
        {
            sparse[0][i] = a[i];
        }
 
        for (int lg = 1 ; (1 << lg) <= n ; ++lg)
        {
            for (int i = 1 ; i + (1 << lg) - 1 <= n ; ++i)
            {
                sparse[lg][i] = std::max(sparse[lg - 1][i], sparse[lg - 1][i + (1 << lg - 1)]);
            }
        }
 
        for (int i = 1 ; i <= n ; ++i)
        {
            getLOG[i] = getLOG[i - 1];
            if ((1 << getLOG[i] + 1) < i) getLOG[i]++;
        }
    }
 
    int findMAX(int l, int r)
    {
        int lg = getLOG[r - l + 1];
        return std::max(sparse[lg][l], sparse[lg][r - (1 << lg) + 1]);
    }
};
 
Sparse sparse;
llong solve()
{
    for (int i = 1 ; i <= n ; ++i)
    {
        map[i][0] = ++cnt;
    }
 
    sparse.build(h);
    for (int i = 1 ; i <= m ; ++i)
    {
        int prev = left[i];
        if (map[left[i]][y[i]] == 0)
        {
            map[left[i]][y[i]] = ++cnt;
        }
 
        while (prev < right[i])
        {
            int l = prev, r = right[i] + 1, mid;
            while (l < r - 1)
            {
                mid = l + r >> 1;
                if (sparse.findMAX(prev + 1, mid) < y[i]) l = mid;
                else r = mid;
            }
 
            if (map[r][y[i]] == 0)
            {
                map[r][y[i]] = ++cnt;
            }
 
            // std::cout << "here: " << prev << ' ' << r << ' ' << y[i] << '\n';
            g[map[prev][y[i]]].push_back({map[r][y[i]], x[r] - x[prev]});
            g[map[r][y[i]]].push_back({map[prev][y[i]], x[r] - x[prev]});
            prev = r;
        }
    }
 
    for (int i = 1 ; i <= n ; ++i)
    {
        auto prev = map[i].begin();
        for (auto curr = std::next(map[i].begin()) ; curr != map[i].end() ; ++curr)
        {
            // std::cout << "edge ver: " << x[i] << ' ' << prev->first << ' ' << x[i] << ' ' << curr->first << '\n';
            g[prev->second].push_back({curr->second, curr->first - prev->first});
            g[curr->second].push_back({prev->second, curr->first - prev->first});
            prev = curr;
        }
    }
 
    std::priority_queue <std::pair <llong,int>> pq;
    std::fill(dist + 1, dist + 1 + cnt, INF);
    pq.push({0, map[s][0]});
    dist[map[s][0]] = 0;
 
    while (pq.size())
    {
        auto [d, node] = pq.top();
        pq.pop();
 
        if (vis[node])
        {
            continue;
        }
 
        vis[node] = true;
        for (const auto &[u, ed] : g[node])
        {
            if (dist[u] > dist[node] + ed)
            {
                dist[u] = dist[node] + ed;
                pq.push({-dist[u], u});
            }
        }
    }
 
	return (dist[map[t][0]] == INF ? -1 : dist[map[t][0]]);
}
 
llong dpL[MAXN];
llong dpR[MAXN];
llong solveSpecial()
{
    for (int i = 1 ; i <= m ; ++i)
    {
        if (left[i] == 1)
        {
            dpL[i] = y[i];
            dpR[i] = y[i] + x[right[i]];
        } else
        {
            dpL[i] = INF;
            dpR[i] = INF;
            for (int j = 1 ; j < i ; ++j)
            {
                if (right[j] >= left[i])
                {
                    if (y[j] < y[i])
                    {
                        dpL[i] = std::min(dpL[i], dpL[j] + x[left[i]] - x[left[j]] + y[i] - y[j]);
                    }
 
                    if (y[j] >= y[i] && y[j] <= h[left[i]])
                    {
                        dpL[i] = std::min(dpL[i], dpL[j] + x[left[i]] - x[left[j]] + y[j] - y[i]);
                    }
                } 
 
                if (left[i] <= right[j])
                {
                    if (y[j] >= y[i])
                    {
                        dpR[i] = std::min(dpR[i], dpR[j] + y[j] - y[i] + x[right[i]] - x[right[j]]);
                    }
 
                    if (y[j] <= y[i] && y[i] <= h[right[j]])
                    {
                        dpR[i] = std::min(dpR[i], dpR[j] + y[i] - y[j] + x[right[i]] - x[right[j]]);
                    }
                }
            }
 
            dpR[i] = std::min(dpR[i], dpL[i] + x[right[i]] - x[left[i]]);
        }
    }
 
    llong ans = INF;
    for (int i = 1 ; i <= m ; ++i)
    {
        if (right[i] == n)
        {
            ans = std::min(ans, dpR[i] + y[i]);
        }
    }
 
    return ans;
}
 
long long min_distance(std::vector<int> x, std::vector<int> h, std::vector<int> l, std::vector<int> r, std::vector<int> y, int s, int t) 
{
    n = x.size();
    m = l.size();
    ::s = s + 1; ::t = t + 1;
 
    for (int i = 0 ; i < n ; ++i)
    {
        ::h[i + 1] = h[i];
        ::x[i + 1] = x[i];
    }
 
    std::vector <int> perm(m);
    std::iota(perm.begin(), perm.end(), 0);
    std::sort(perm.begin(), perm.end(), [&](int x, int y)
    {
        return l[x] < l[y];
    });
 
    for (int i = 0 ; i < m ; ++i)
    {
        ::left[i + 1] = l[perm[i]] + 1;
        ::right[i + 1] = r[perm[i]] + 1;
        ::y[i + 1] = y[perm[i]];
    }
 
    if (::s == 1 && ::t == n) return solveSpecial();
    return solve();
}

Compilation message

walk.cpp: In member function 'void Sparse::build(int*)':
walk.cpp:51:89: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   51 |                 sparse[lg][i] = std::max(sparse[lg - 1][i], sparse[lg - 1][i + (1 << lg - 1)]);
      |                                                                                      ~~~^~~
walk.cpp:58:33: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
   58 |             if ((1 << getLOG[i] + 1) < i) getLOG[i]++;
      |                       ~~~~~~~~~~^~~
walk.cpp: In function 'llong solve()':
walk.cpp:91:25: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   91 |                 mid = l + r >> 1;
      |                       ~~^~~
walk.cpp: At global scope:
walk.cpp:32:9: warning: '{anonymous}::cntNodes' defined but not used [-Wunused-variable]
   32 |     int cntNodes;
      |         ^~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 40328 KB Output is correct
2 Correct 15 ms 40284 KB Output is correct
3 Correct 16 ms 40280 KB Output is correct
4 Correct 16 ms 40284 KB Output is correct
5 Correct 16 ms 40324 KB Output is correct
6 Correct 16 ms 40540 KB Output is correct
7 Correct 17 ms 40280 KB Output is correct
8 Correct 16 ms 40284 KB Output is correct
9 Correct 16 ms 40292 KB Output is correct
10 Correct 17 ms 40540 KB Output is correct
11 Correct 16 ms 40284 KB Output is correct
12 Correct 16 ms 40284 KB Output is correct
13 Correct 16 ms 40284 KB Output is correct
14 Correct 19 ms 40212 KB Output is correct
15 Correct 16 ms 40284 KB Output is correct
16 Correct 16 ms 40284 KB Output is correct
17 Correct 16 ms 40280 KB Output is correct

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 40280 KB Output is correct
2 Correct 16 ms 40192 KB Output is correct
3 Correct 515 ms 137252 KB Output is correct
4 Correct 336 ms 153940 KB Output is correct
5 Correct 211 ms 138684 KB Output is correct
6 Correct 188 ms 128084 KB Output is correct
7 Correct 237 ms 138832 KB Output is correct
8 Correct 695 ms 164176 KB Output is correct
9 Correct 273 ms 136372 KB Output is correct
10 Correct 560 ms 194380 KB Output is correct
11 Correct 221 ms 96084 KB Output is correct
12 Correct 1772 ms 52044 KB Output is correct
13 Incorrect 1809 ms 52044 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 438 ms 43860 KB Output is correct
2 Execution timed out 4022 ms 47264 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 438 ms 43860 KB Output is correct
2 Execution timed out 4022 ms 47264 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 40328 KB Output is correct
2 Correct 15 ms 40284 KB Output is correct
3 Correct 16 ms 40280 KB Output is correct
4 Correct 16 ms 40284 KB Output is correct
5 Correct 16 ms 40324 KB Output is correct
6 Correct 16 ms 40540 KB Output is correct
7 Correct 17 ms 40280 KB Output is correct
8 Correct 16 ms 40284 KB Output is correct
9 Correct 16 ms 40292 KB Output is correct
10 Correct 17 ms 40540 KB Output is correct
11 Correct 16 ms 40284 KB Output is correct
12 Correct 16 ms 40284 KB Output is correct
13 Correct 16 ms 40284 KB Output is correct
14 Correct 19 ms 40212 KB Output is correct
15 Correct 16 ms 40284 KB Output is correct
16 Correct 16 ms 40284 KB Output is correct
17 Correct 16 ms 40280 KB Output is correct
18 Correct 19 ms 40280 KB Output is correct
19 Correct 16 ms 40192 KB Output is correct
20 Correct 515 ms 137252 KB Output is correct
21 Correct 336 ms 153940 KB Output is correct
22 Correct 211 ms 138684 KB Output is correct
23 Correct 188 ms 128084 KB Output is correct
24 Correct 237 ms 138832 KB Output is correct
25 Correct 695 ms 164176 KB Output is correct
26 Correct 273 ms 136372 KB Output is correct
27 Correct 560 ms 194380 KB Output is correct
28 Correct 221 ms 96084 KB Output is correct
29 Correct 1772 ms 52044 KB Output is correct
30 Incorrect 1809 ms 52044 KB Output isn't correct
31 Halted 0 ms 0 KB -