oj.uz

Submission #310885

# Submission time Handle Problem Language Result Execution time Memory
310885 2020-10-08T10:59:05 Z fishy15 Olympic Bus (JOI20_ho_t4) C++14
26 / 100
 237 ms 3576 KB 
#include <iostream>
#include <iomanip>
#include <fstream>
#include <vector>
#include <array>
#include <algorithm>
#include <utility>
#include <map>
#include <queue>
#include <set>
#include <cmath>
#include <cstdio>
#include <cstring>

#define ll unsigned long long
#define ld long double
#define eps 1e-8
#define MOD 1000000007

#define INF 0x3f3f3f3f
#define INFLL 0x003f3f3f3f3f3f3f

// change if necessary
#define MAXN 210

using namespace std;

int n, m;
vector<array<int, 3>> adj[MAXN];
vector<array<int, 3>> radj[MAXN];
ll ans = INFLL;

ll dist_1[MAXN];
ll rdist_1[MAXN];
ll dist_n[MAXN];
ll rdist_n[MAXN];
bool vis[MAXN];

void solve(int rem) {
    for (int i = 0; i < n; i++) {
        dist_1[i] = INFLL;
        dist_n[i] = INFLL;
        rdist_1[i] = INFLL;
        rdist_n[i] = INFLL;
    }

    memset(vis, 0, sizeof vis);

    priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> pq;
    pq.push({0, 0});
    while (!pq.empty()) {
        auto [d, e] = pq.top();
        pq.pop();
        if (vis[e]) continue;
        vis[e] = true;
        dist_1[e] = d;
        if (e == rem) continue;
        for (auto [u, c, dd] : adj[e]) {
            if (!vis[u] && d + c < dist_1[u]) {
                pq.push({d + c, u});
                dist_1[u] = d + c;
            }
        }
    }

    memset(vis, 0, sizeof vis);
    pq.push({0, n - 1});
    while (!pq.empty()) {
        auto [d, e] = pq.top();
        pq.pop();
        if (vis[e]) continue;
        vis[e] = true;
        rdist_n[e] = d;
        for (auto [u, c, dd] : radj[e]) {
            if (!vis[u] && d + c < rdist_n[u] && u != rem) {
                pq.push({d + c, u});
                rdist_n[u] = d + c;
            }
        }
    }

    memset(vis, 0, sizeof vis);
    pq.push({0, n - 1});
    while (!pq.empty()) {
        auto [d, e] = pq.top();
        pq.pop();
        if (vis[e]) continue;
        vis[e] = true;
        dist_n[e] = d;
        if (e == rem) continue;
        for (auto [u, c, dd] : adj[e]) {
            if (!vis[u] && d + c < dist_n[u]) {
                pq.push({d + c, u});
                dist_n[u] = d + c;
            }
        }
    }

    memset(vis, 0, sizeof vis);
    pq.push({0, 0});
    while (!pq.empty()) {
        auto [d, e] = pq.top();
        pq.pop();
        if (vis[e]) continue;
        vis[e] = true;
        rdist_1[e] = d;
        for (auto [u, c, dd] : radj[e]) {
            if (!vis[u] && d + c < rdist_1[u] && u != rem) {
                pq.push({d + c, u});
                rdist_1[u] = d + c;
            }
        }
    }

    /* cout << "rem " << rem << '\n'; */
    /* for (int i = 0; i < n; i++) { */
    /*     cout << dist_1[i] << ' '; */
    /* } */
    /* cout << '\n'; */
    /* for (int i = 0; i < n; i++) { */
    /*     cout << dist_n[i] << ' '; */
    /* } */
    /* cout << '\n'; */
    /* for (int i = 0; i < n; i++) { */
    /*     cout << rdist_n[i] << ' '; */
    /* } */
    /* cout << '\n'; */
    /* for (int i = 0; i < n; i++) { */
    /*     cout << rdist_1[i] << ' '; */
    /* } */
    /* cout << '\n'; */

    ans = min(ans, dist_1[n - 1] + dist_n[0]);
    if (rem == n || adj[rem].empty()) return;

    // path without flipping
    pair<ll, ll> max_to_n = {dist_1[n - 1], dist_1[n - 1]};
    pair<ll, ll> max_to_1 = {dist_n[0], dist_n[0]};
    pair<ll, ll> r_max_to_1 = {rdist_1[rem], rdist_1[rem]};
    pair<ll, ll> r_max_to_n = {rdist_n[rem], rdist_n[rem]};

    for (const auto &e : adj[rem]) {
        ll to_n = dist_1[rem] + e[1] + rdist_n[e[0]];
        ll to_1 = dist_n[rem] + e[1] + rdist_1[e[0]];

        if (to_n <= max_to_n.first) {
            max_to_n.second = max_to_n.first;
            max_to_n.first = to_n;
        } else if (to_n < max_to_n.second) {
            max_to_n.second = to_n;
        }

        if (to_1 <= max_to_1.first) {
            max_to_1.second = max_to_1.first;
            max_to_1.first = to_1;
        } else if (to_1 < max_to_1.second) {
            max_to_1.second = to_1;
        }

        // no flip best prev path
        ll r_to_n = e[1] + rdist_n[e[0]];
        ll r_to_1 = e[1] + rdist_1[e[0]];

        if (r_to_n <= r_max_to_1.first) {
            r_max_to_n.second = r_max_to_n.first;
            r_max_to_n.first = r_to_n;
        } else if (r_to_n < r_max_to_1.second) {
            r_max_to_1.second = r_to_n;
        }

        if (r_to_1 <= r_max_to_1.first) {
            r_max_to_1.second = r_max_to_1.first;
            r_max_to_1.first = r_to_1;
        } else if (r_to_1 < r_max_to_1.second) {
            r_max_to_1.second = r_to_1;
        }
    }

    /* cout << max_to_n.first << ' ' << max_to_n.second << '\n'; */
    /* cout << max_to_1.first << ' ' << max_to_1.second << '\n'; */

    // consider flipping this
    for (const auto &e : adj[rem]) {
        ll to_n = dist_1[rem] + e[1] + rdist_n[e[0]];
        ll r_to_n = e[1] + rdist_n[e[0]];
        if (to_n == max_to_n.first) {
            to_n = max_to_n.second;
        } else {
            to_n = max_to_n.first;
        }
        if (r_to_n == r_max_to_n.first) {
            r_to_n = r_max_to_n.second;
        } else {
            r_to_n = r_max_to_n.first;
        }
        to_n = min(to_n, dist_1[e[0]] + e[1] + r_to_n);

        ll to_1 = dist_n[rem] + e[1] + rdist_1[e[0]];
        ll r_to_1 = e[1] + rdist_1[e[0]];
        if (to_1 == max_to_1.first) {
            to_1 = max_to_1.second;
        } else {
            to_1 = max_to_1.first;
        }
        if (r_to_1 == r_max_to_1.first) {
            r_to_1 = r_max_to_1.second;
        } else {
            r_to_1 = r_max_to_1.first;
        }
        to_1 = min(to_1, dist_n[e[0]] + e[1] + r_to_1);

        ans = min(ans, to_n + to_1 + e[2]);
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(0);

    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        int u, v, c, d; cin >> u >> v >> c >> d;
        u--; v--;
        adj[u].push_back({v, c, d});
        radj[v].push_back({u, c, d});
    }

    for (int i = 0; i <= n; i++) {
        solve(i);
    }

    if (ans == INFLL) {
        cout << "-1\n";
    } else {
        cout << ans << '\n';
    }

    return 0;
}

Compilation message

ho_t4.cpp: In function 'void solve(int)':
ho_t4.cpp:52:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   52 |         auto [d, e] = pq.top();
      |              ^
ho_t4.cpp:58:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   58 |         for (auto [u, c, dd] : adj[e]) {
      |                   ^
ho_t4.cpp:69:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   69 |         auto [d, e] = pq.top();
      |              ^
ho_t4.cpp:74:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   74 |         for (auto [u, c, dd] : radj[e]) {
      |                   ^
ho_t4.cpp:85:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   85 |         auto [d, e] = pq.top();
      |              ^
ho_t4.cpp:91:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   91 |         for (auto [u, c, dd] : adj[e]) {
      |                   ^
ho_t4.cpp:102:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  102 |         auto [d, e] = pq.top();
      |              ^
ho_t4.cpp:107:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  107 |         for (auto [u, c, dd] : radj[e]) {
      |                   ^

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 25 ms 384 KB Output is correct
4 Correct 26 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 35 ms 384 KB Output is correct
11 Correct 35 ms 384 KB Output is correct
12 Correct 34 ms 384 KB Output is correct
13 Correct 7 ms 512 KB Output is correct
14 Correct 16 ms 384 KB Output is correct
15 Correct 16 ms 512 KB Output is correct
16 Correct 17 ms 384 KB Output is correct

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 237 ms 2424 KB Output is correct
2 Correct 215 ms 2304 KB Output is correct
3 Correct 219 ms 3456 KB Output is correct
4 Correct 27 ms 512 KB Output is correct
5 Correct 14 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 96 ms 3448 KB Output is correct
10 Correct 95 ms 3576 KB Output is correct
11 Incorrect 164 ms 3576 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 384 KB Output is correct
2 Correct 3 ms 384 KB Output is correct
3 Correct 175 ms 1664 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 209 ms 2176 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 81 ms 2168 KB Output is correct
9 Correct 82 ms 3200 KB Output is correct
10 Correct 162 ms 3192 KB Output is correct
11 Correct 164 ms 3200 KB Output is correct
12 Correct 161 ms 3328 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 0 ms 384 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 166 ms 3420 KB Output is correct
20 Correct 161 ms 3192 KB Output is correct
21 Correct 161 ms 3192 KB Output is correct
22 Correct 164 ms 3328 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 25 ms 384 KB Output is correct
4 Correct 26 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 35 ms 384 KB Output is correct
11 Correct 35 ms 384 KB Output is correct
12 Correct 34 ms 384 KB Output is correct
13 Correct 7 ms 512 KB Output is correct
14 Correct 16 ms 384 KB Output is correct
15 Correct 16 ms 512 KB Output is correct
16 Correct 17 ms 384 KB Output is correct
17 Correct 237 ms 2424 KB Output is correct
18 Correct 215 ms 2304 KB Output is correct
19 Correct 219 ms 3456 KB Output is correct
20 Correct 27 ms 512 KB Output is correct
21 Correct 14 ms 384 KB Output is correct
22 Correct 4 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 96 ms 3448 KB Output is correct
26 Correct 95 ms 3576 KB Output is correct
27 Incorrect 164 ms 3576 KB Output isn't correct
28 Halted 0 ms 0 KB -