Submission #1235835

#	Time	Username	Problem	Language	Result	Execution time	Memory
1235835		iamhereforfun	Robot (JOI21_ho_t4)	C++20	100 / 100	79 ms	15348 KiB

Main

// IamHereForFun //

#include <bits/stdc++.h>

using namespace std;

#define LSOne(X) ((X) & -(X))

const int N = 1e5 + 5;
const int M = 2e5 + 5;
const int L = 12;
const int LG = 25;
const int P = 37;
const long long INF = 1e18 + 5;
const int MOD = 1e9 + 7;
const int nx[] = {0, -1, 0, 1}, ny[] = {-1, 0, 1, 0};

int n, m;
vector<array<int, 3>> adj[N];
long long dp[N], col[M], sum[M];
bool vis[N];

void solve()
{
    cin >> n >> m;
    for (int x = 0; x < m; x++)
    {
        int a, b, c, p;
        cin >> a >> b >> c >> p;
        adj[a].push_back({b, c, p});
        adj[b].push_back({a, c, p});
    }
    for (int x = 1; x <= n; x++)
    {
        dp[x] = INF;
        vis[x] = 0;
    }
    priority_queue<pair<long long, int>> pq;
    pq.push({0, 1});
    dp[1] = 0;
    while (!pq.empty())
    {
        int i = pq.top().second;
        pq.pop();
        if (vis[i])
            continue;
        vis[i] = true;
        for (array<int, 3> &a : adj[i])
        {
            sum[a[1]] = 0;
            col[a[1]] = INF;
        }
        for (array<int, 3> &a : adj[i])
        {
            sum[a[1]] += a[2];
            col[a[1]] = min(col[a[1]], dp[a[0]]);
        }
        for (array<int, 3> &a : adj[i])
        {
            long long val = min({dp[i] + a[2], dp[i] + sum[a[1]] - a[2], sum[a[1]] + col[a[1]] - a[2]});
            int j = a[0];
            if (val < dp[j])
            {
                dp[j] = val;
                pq.push({-dp[j], j});
            }
        }
    }
    if (dp[n] == INF)
        cout << -1;
    else
        cout << dp[n];
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
    // cin >> t;
    for (int x = 1; x <= t; x++)
    {
        solve();
    }
    return 0;
}

• Subtask 1: 34 / 34
• Subtask 2: 24 / 24
• Subtask 3: 42 / 42