Submission #924376

#	Time	Username	Problem	Language	Result	Execution time	Memory
924376		yeediot	Olympic Bus (JOI20_ho_t4)	C++14	0 / 100	1051 ms	3680 KiB

ho_t4

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int,int>
#define sz(x) (int)(x.size())
#define all(x) x.begin(),x.end()
#define F first
#define S second
#define pb push_back
#ifdef local
void setio(){freopen("/Users/iantsai/Library/Mobile Documents/com~apple~CloudDocs/cpp/Empty.md","r",stdin);}
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
void setio(){}
#define debug(x...)
#endif
struct edge{
    int a,b,c,d;
};
const int mxn=205;
vector<edge>e;
vector<pii>adj[mxn];
int dij(int st,int ed){
    vector<int>dis(mxn);
    for(int i=0;i<mxn;i++)dis[i]=2e18;
    dis[st]=0;
    priority_queue<pii,vector<pii>,greater<pii>>pq;
    pq.push({0,st});
    while(sz(pq)){
        auto [d,v]=pq.top();
        pq.pop();
        if(dis[v]<d)continue;
        for(auto [u,dd]:adj[v]){
            if(dis[v]+dd<dis[u]){
                dis[u]=dis[v]+dd;
                pq.push({dis[u],u});
            }
        }
    }
    return dis[ed];
}
signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    setio();
    int n,m;
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int a,b,c,d;
        cin>>a>>b>>c>>d;
        e.pb({a,b,c,d});
        adj[a].pb({b,c});
    }
    int ans=dij(1,n)+dij(n,1);
    for(int i=0;i<m;i++){
        for(int j=1;j<=n;j++){
            adj[j].clear();
        }
        for(int j=0;j<m;j++){
            if(j==i)continue;
            auto [a,b,c,d]=e[j];
            adj[a].pb({b,c});
        }
        adj[e[i].b].pb({e[i].a,e[i].c});
        int temp=e[i].d;
        temp+=dij(1,n)+dij(n,1);
        ans=min(ans,temp);
    }
    cout<<ans<<'\n';
}
/*
*/

Compilation message (stderr)

ho_t4.cpp: In function 'long long int dij(long long int, long long int)':
ho_t4.cpp:30:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   30 |         auto [d,v]=pq.top();
      |              ^
ho_t4.cpp:33:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   33 |         for(auto [u,dd]:adj[v]){
      |                  ^
ho_t4.cpp: In function 'int main()':
ho_t4.cpp:61:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   61 |             auto [a,b,c,d]=e[j];
      |                  ^

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63