Submission #650164

#	Time	Username	Problem	Language	Result	Execution time	Memory
650164		HaYoungJoon	Robot (JOI21_ho_t4)	C++14	0 / 100	3059 ms	79560 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define INF 1e18

using namespace std;

const int maxn = 1e5 + 1;
typedef pair<ll,ll> pii;
typedef pair<ll,pii> piii;
typedef pair<ll,piii> piiii;
unordered_map<int,ll> dp[maxn], cost[maxn];
vector<piii> adj[maxn];
int n,m;

ll dijsktra() {
    for (int i = 1; i <= n; i++) {
        dp[i][0] = INF;
        for (piii j: adj[i]) {
            int c = j.se.fi;
            dp[i][c] = INF;
        }
    }
    dp[1][0] = 0;
    priority_queue<piiii, vector<piiii>, greater<piiii> > pq;
    pq.push(piiii(0,piii(0,pii(1,0))));
    while (!pq.empty()) {
        int u = pq.top().se.se.fi, oldcol = pq.top().se.se.se;
        ll D = pq.top().fi, used = - pq.top().se.fi;
        pq.pop();
        if (D > dp[u][oldcol]) continue;
        if (u == n) return D;
        for (piii i: adj[u]) {
            int v = i.fi, newcol = i.se.fi;
            ll w = i.se.se;
            if (oldcol == 0) {
                /// Ko doi mau (u,v) -> doi mau cac canh con lai
                if (dp[v][0] > D + cost[u][newcol] - w) {
                    dp[v][0] = D + cost[u][newcol] - w;
                    pq.push(piiii(dp[v][0],piii(0,pii(v,0))));
                }
                ///
                /// Doi mau (u,v)
                if (dp[v][newcol] > D + w) {
                    dp[v][newcol] = D + w;
                    pq.push(piiii(dp[v][newcol],piii(-w,pii(v,newcol))));
                }
            } else {
                /// Ko doi mau (u,v) -> doi mau cac canh con lai
                if (dp[v][0] > D + cost[u][newcol] - w - (newcol == oldcol)*used) {
                    dp[v][0] = D + cost[u][newcol] - w - (newcol == oldcol)*used;
                    pq.push(piiii(dp[v][0],piii(0,pii(v,0))));
                }
                ///
                /// Doi mau (u,v)
                if (dp[v][newcol] > D + w) {
                    dp[v][newcol] = D + w;
                    pq.push(piiii(dp[v][newcol],piii(-w,pii(v,newcol))));
                }
                /// Doi mau (u,v) va cac canh con lai
                if (dp[v][newcol] > D + cost[u][newcol] - (newcol == oldcol)*used) {
                    dp[v][newcol] = D + w;
                    pq.push(piiii(dp[v][newcol],piii(-w,pii(v,newcol))));
                }
            }
        }
    }
    return -1;
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        ll u,v,c,w;
        cin >> u >> v >> c >> w;
        adj[u].push_back(piii(v,pii(c,w)));
        adj[v].push_back(piii(u,pii(c,w)));
        cost[u][c] += w;
        cost[v][c] += w;
    }
    cout << dijsktra();
    return 0;
}
/*
6 4
1 2 1 1000000000
2 3 1 1000000000
3 4 1 1000000000
4 5 1 1000000000

*/

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