Submission #1026554

#	Time	Username	Problem	Language	Result	Execution time	Memory
1026554		dwuy	Robot (JOI21_ho_t4)	C++14	100 / 100	780 ms	115112 KiB

Main

///   - dwuy -
#include <bits/stdc++.h>

#define fastIO ios_base::sync_with_stdio(false); cin.tie(NULL)
#define file(a) freopen(a".inp","r",stdin); freopen(a".out", "w",stdout)
#define fi first
#define se second
#define endl "\n"
#define len(s) (int)((s).size())
#define MASK(k)(1LL<<(k))
#define TASK "test"
#define int long long

using namespace std;

typedef tuple<int, int, int> tpiii;
typedef pair<double, double> pdd;
typedef pair<int, int> pii;
typedef long long ll;

const long long OO = 1e18;
const int MOD = 1e9 + 7;
const int INF = 1e9;
const int MX = 200005;

struct Edge{
    int u, v, c, col;

    Edge(int u=0, int v=0, int col=0, int c=0){
        this->u = u;
        this->v = v;
        this->col = col;
        this->c = c;
    }

    int other(int x){
        return u ^ v ^ x;
    }
};

int n, m;
Edge edges[MX];
vector<int> G[MX];
map<int, vector<int>> T[MX]; 

void nhap(){
    cin >> n >> m;
    for(int i=1; i<=m; i++){
        int u, v, col, c;
        cin >> u >> v >> col >> c;
        edges[i] = Edge(u, v, col, c);
        G[u].push_back(i);
        G[v].push_back(i);
        T[u][col].push_back(i);
        T[v][col].push_back(i);
    }
}

int d[MX];
map<int, int> sum[MX];
map<int, int> f[MX];

void solve(){
    for(int i=1; i<=m; i++){
        int u = edges[i].u;
        int v = edges[i].v;
        int c = edges[i].c;
        int col = edges[i].col;
        sum[u][col] += c;
        sum[v][col] += c;
    }

    priority_queue<tpiii, vector<tpiii>, greater<tpiii>> Q;
    memset(d, 0x3f, sizeof d);
    d[1] = 0;
    Q.push({0, -1, 1});
    while(Q.size()){
        int du, cl, u;
        tie(du, cl, u) = Q.top();
        Q.pop();
        if(cl == -1 && d[u] != du) continue;    
        if(cl != -1 && f[u][cl] != du) continue;
        if(cl == -1){
            for(int i: G[u]){
                int c = edges[i].c;
                int cl = edges[i].col;
                int v = edges[i].other(u);
                int scl = sum[u][cl];
                if(f[v].find(cl) == f[v].end()) f[v][cl] = 1e18;
                if(d[v] > min(du + c , du + scl - c)){
                    d[v] = min(du + c , du + scl - c);
                    Q.push({d[v], -1, v});
                }
                if(f[v][cl] > du){
                    f[v][cl] = du;
                    Q.push({f[v][cl], cl, v});
                }
            }
        }
        else{
            for(int i: T[u][cl]){
                int c = edges[i].c;
                int v = edges[i].other(u);
                int scl = sum[u][cl];
                if(d[v] > du + scl - c){
                    d[v] = du + scl - c;
                    Q.push({d[v], -1, v});
                }
            }
        }
    }
    cout << (d[n] == d[0]? -1 : d[n]);
}

int32_t main(){
    fastIO;
    //file(TASK);

    nhap();
    solve();

    return 0;
}

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