Submission #854713

#	Time	Username	Problem	Language	Result	Execution time	Memory
854713		khanhtai	Wild Boar (JOI18_wild_boar)	C++17	12 / 100	123 ms	984916 KiB

wild_boar

#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define INF 1e18
#define fi first
#define se second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define endl '\n'
#define pi 3.14159265359
#define TASKNAME "wildboar"
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 501;
vector<iii> g[MAXN];
int plan[MAXN];
int n,m,q,l,u,v,w,dist[MAXN][MAXN][MAXN];
bool spec[MAXN];
void dijkstra(){
    memset(dist,0x3f,sizeof(dist));
    dist[plan[1]][1][0] = 0;
    priority_queue<array<int,4>,vector<array<int,4>>,greater<array<int,4>>> pq;
    pq.push({0,plan[1],1,0});
    while(!pq.empty()){
        array<int,4> tp = pq.top();
        int du = tp[0];
        int u = tp[1];
        int cur = tp[2];
        int cur_edge_id = tp[3];
        pq.pop();
        if (du > dist[u][cur][cur_edge_id]) continue;
        for(auto pt: g[u]){
            int v = pt.se.fi;
            int idedge = pt.fi;
            int w = pt.se.se;
            if (cur_edge_id == idedge) continue;
            if (v == plan[cur+1] and dist[v][cur+1][idedge] > dist[u][cur][cur_edge_id] + w){
                dist[v][cur+1][idedge] = dist[u][cur][cur_edge_id] + w;
                pq.push({dist[v][cur+1][idedge],v,cur+1,idedge});
            }
            if (v != plan[cur+1] and dist[v][cur][idedge] > dist[u][cur][cur_edge_id] + w){
                dist[v][cur][idedge] = dist[u][cur][cur_edge_id] + w;
                pq.push({dist[v][cur][idedge],v,cur,idedge});
            }
        }
    }
    int ans = INF;
    for(int i=1;i<=m;i++){
        ans = min(ans, dist[plan[l]][l][i]);
    }
    if (ans == INF) cout<<-1<<endl;
    else cout<<ans<<endl;
}
main()
{
    fast;
 //   freopen(TASKNAME".inp","r",stdin);
 //   freopen(TASKNAME".out","w",stdout);
    cin>>n>>m>>q>>l;
    memset(spec,false,sizeof(spec));
    for(int i=1;i<=m;i++){
        cin>>u>>v>>w;
        g[u].pb({i,{v,w}});
        g[v].pb({i,{u,w}});
    }

    for(int i=1;i<=l;i++){
        cin>>plan[i];
        spec[plan[i]] = true;
    }
    for(int i=1;i<=q;i++){
        int p,k;
        cin>>p>>k;
        spec[plan[p]] = false;
        plan[p] = k;
        spec[plan[p]] = true;
        dijkstra();

    }



}

Compilation message (stderr)

wild_boar.cpp:61:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   61 | main()
      | ^~~~

• Subtask 1: 12 / 12
• Subtask 2: 0 / 35
• Subtask 3: 0 / 15
• Subtask 4: 0 / 38