Submission

Score: 100

User: august

Problemset: รถยนต์ รถไฟ เรือเมล์ ลิเก ตำรวจ

Language: cpp

Time: 0.009 second

Submitted On: 2026-03-11 13:11:20

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pi pair<int,int>

const int INF = 1e18, N = 401;

bool g[N][N];

int32_t main() {
    cin.tie(0)->sync_with_stdio(0);
    int n,m;
    cin>> n>> m;

    for (int i=0; i<m; i++) {
        int u,v;
        cin>> u>> v;
        g[u][v] = g[v][u] = 1;
    }

    vector<int> dist(n+1, INF), dist1(n+1, INF);
    priority_queue<pi, vector<pi>, greater<pi>> pq;

    pq.push({0, 1});
    dist[1] = 0;

    while (!pq.empty()) {
        pi cur = pq.top();
        pq.pop();

        int d=cur.first, u=cur.second;

        if (d > dist[u]) continue;

        for (int v=1; v<=n; v++) {
            if (!g[u][v] || v==u) continue;

            if (dist[v] > dist[u]+10*abs(v-u)) {
                dist[v] = dist[u]+10*abs(v-u);
                pq.push({dist[v], v});
            }
        }
    }
    pq.push({0, 1});
    dist1[1] = 0;

    while (!pq.empty()) {
        pi cur = pq.top();
        pq.pop();

        int d=cur.first, u=cur.second;

        if (d > dist1[u]) continue;

        for (int v=1; v<=n; v++) {
            if (g[u][v] || v==u) continue;

            if (dist1[v] > dist1[u]+10*abs(v-u)) {
                dist1[v] = dist1[u]+10*abs(v-u);
                pq.push({dist1[v], v});
            }
        }
    }

    if (dist[n] == INF || dist1[n] == INF) cout<< -1;
    else cout<< max(dist[n], dist1[n]);
}