Submission #565711

#	Time	Username	Problem	Language	Result	Execution time	Memory
565711		RealSnake	Evacuation plan (IZhO18_plan)	C++14	0 / 100	12 ms	468 KiB

plan

#include "bits/stdc++.h"
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

#define ll long long
#define mod 1000000007

ofstream fout(".out");
ifstream fin(".in");

vector<pair<int, int>> v[1001];
int d[1001], g[1001];
bool vis[1001], vis2[1001];
int n, m, s, t, o;

int dfs2(int x) {
    if(!d[x])
        return 0;
    if(g[x])
        return g[x];
    vis2[x] = 1;
    int y = 1e9;
    for(auto i : v[x]) {
        if(!vis2[i.first])
            y = min(y, dfs2(i.first) + i.second);
    }
    g[x] = y;
    vis2[x] = 0;
    return y;
}

int dfs(int x) {
    if(x == t)
        return d[x];
    if(d[x] == 1e9) {
        for(int i = 1; i <= n; i++)
            g[i] = 0;
        d[x] = dfs2(x);
    }
    vis[x] = 1;
    int mx = 0, o = 0;
    for(auto i : v[x]) {
        if(!vis[i.first]) {
            mx = max(mx, dfs(i.first));
            o = 1;
        }
    }
    vis[x] = 0;
    if(!o)
        return 1e9;
    return min(d[x], mx);
}

signed main() {

    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    cin >> n >> m;
    for(int i = 1; i <= n; i++)
        d[i] = 1e9;
    for(int i = 0; i < m; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        v[a].push_back({b, c});
        v[b].push_back({a, c});
    }
    int k;
    cin >> k;
    for(int i = 0; i < k; i++) {
        int x;
        cin >> x;
        d[x] = 0;
    }
    int q;
    cin >> q;
    while(q--) {
        cin >> s >> t;
        if(d[s] == 1e9) {
            for(int i = 1; i <= n; i++)
                g[i] = 0;
            d[s] = dfs2(s);
        }
        if(d[t] == 1e9) {
            for(int i = 1; i <= n; i++)
                g[i] = 0;
            d[t] = dfs2(t);
        }
        bool b = 0;
        for(auto i : v[s]) {
            if(i.first == t) {
                b = 1;
                break;
            }
        }
        if(b) {
            cout << min(d[s], d[t]) << "\n";
            continue;
        }
        cout << dfs(s) << "\n";
    }

    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 13
• Subtask 3: 0 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 46