Submission #1020629

#	Time	Username	Problem	Language	Result	Execution time	Memory
1020629		Kodik	Robot (JOI21_ho_t4)	C++17	0 / 100	94 ms	35380 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define ss second
#define ff first
typedef long long ll;
#define int ll
int mod = 1e9+7;
int inf = 1e18;

struct edge{
    int to, c, p;
};


map<int, vector<edge>> graph[100001];
int dp[100001];
map<int, int> dp2[100001], psum[100001];

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    // ifstream cin ("shortcut.in");
    // ofstream cout ("shortcut.out");
    int n, m;
    cin >> n >> m;
    for(int i = 0; i < m; ++i){
        int u, v, c, p;
        cin >> u >> v >> c >> p;
        graph[u][c].push_back({v,c,p});
        graph[v][c].push_back({u,c,p});
        psum[u][c] += p;
        psum[v][c] += p;
    }
    memset(dp, 0x3f, sizeof dp);
    dp[1] = 0;
    using fud  = tuple<int,int,int>; 
    priority_queue<fud> pq;
    pq.push({0,1,0});
    while(!pq.empty()){
        auto[cost,node,c] = pq.top(); pq.pop();
        if(c){
            if(dp2[node][c]!=-cost) continue;
            for(edge &i : graph[node][c]){
                int case1 = psum[node][c] - i.p;
                if(case1 - cost < dp[i.to]){
                    dp[i.to] = case1 - cost;
                    pq.push({-dp[i.to], i.to, 0});
                }
            }
        }else{
            if(dp[node]!=-cost) continue;
            for(auto &i : graph[node]){
                for(edge j : i.ss){
                    int case1 = psum[node][j.c] - j.p - cost;
                    if(case1<dp[j.to]){
                        dp[j.to] = case1;
                        pq.push({-dp[j.to], j.to, 0});
                    }
                    int case2 = j.p - cost;
                    if(case2<dp[j.to]){
                        dp[j.to] = case2;
                        pq.push({dp[j.to], j.to, 0});
                    }
                    int case3 = -cost;
                    if(!dp2[j.to].count(j.c)||case3<dp2[j.to][j.c]){
                        dp2[j.to][j.c] = case3;
                        pq.push({-dp2[j.to][j.c],j.to, j.c});
                    }
                }
            }
        }
    }
    cout << (dp[n]>inf?-1:dp[n]) << '\n';
 
 
    return 0;   
}

• Subtask 1: 0 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42