Submission #1023610

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023610		vjudge1	Robot (JOI21_ho_t4)	C++17	100 / 100	154 ms	96696 KiB

Main

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

#define ll long long
#define ld long double
#define ull unsigned long long
#define pii pair<int,int>
#define pll pair<long long, long long>
#define fi first
#define se second
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define lwb lower_bound
#define upb upper_bound

#define TASKNAME "NAME"

void init()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    ///freopen(TASKNAME".INP","r",stdin); freopen(TASKNAME".OUT","w",stdout);
}

const int SZ = 2e6+5;
const ll INF = INT_MAX / 2, MOD = 1e9+7, INFLL = 2e18;
const double epsilon = 1e-3;

int n,m;

struct Edge
{
    int v, c;
    ll p;
    Edge(int _v = 0, int _c = 0, ll _p = 0) : v(_v), c(_c), p(_p) {}
};

vector<Edge> adj[SZ];
ll dp[SZ], sum[SZ], mn[SZ];

struct Node
{
    int u;
    ll d;
    Node(int _u = 0, ll _d = 0) : u(_u), d(_d) {}

    bool operator < (const Node& other) const
    {
        return d > other.d;
    }
};

priority_queue<Node> pq;

int main()
{
    init();
    cin >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        int u, v, c;
        ll p;
        cin >> u >> v >> c >> p;
        adj[u].pb({v, c, p});
        adj[v].pb({u, c, p});
    }
    for(int i = 1; i < SZ; i++)
    {
        dp[i] = INFLL;
        mn[i] = INFLL;
    }
    dp[1] = 0;
    pq.push({1, 0});
    while(!pq.empty())
    {
        int u = pq.top().u;
        ll d = pq.top().d;
        pq.pop();
        if(d > dp[u]) continue;
        for(Edge e : adj[u])
        {
            int v = e.v, c = e.c;
            ll p = e.p;
            mn[c] = min(mn[c], dp[v]);
            sum[c] += p;
        }
        for(Edge e : adj[u])
        {
            int v = e.v, c = e.c;
            ll p = e.p;
            if(dp[v] > dp[u] + min(p, sum[c] - p))
            {
                dp[v] = dp[u] + min(p, sum[c] - p);
                pq.push({v, dp[v]});
            }
            if(dp[v] > mn[c] + sum[c] - p )
            {
                dp[v] = mn[c] + sum[c] - p;
                pq.push({v, dp[v]});
            }
        }
        for(Edge e : adj[u])
        {
            int v = e.v, c = e.c;
            ll p = e.p;
            mn[c] = INFLL;
            sum[c] -= p;
        }
    }
    cout << (dp[n] == INFLL ? -1 : dp[n]);
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:103:17: warning: unused variable 'v' [-Wunused-variable]
  103 |             int v = e.v, c = e.c;
      |                 ^

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