Submission #924011

#	Time	Username	Problem	Language	Result	Execution time	Memory
924011		winter0101	Olympic Bus (JOI20_ho_t4)	C++14	100 / 100	691 ms	4792 KiB

ho_t4

#include<bits/stdc++.h>
using namespace std;
#define all(fl) fl.begin(),fl.end()
#define pb push_back
#define fi first
#define se second
#define for1(i,j,k) for(int i=j;i<=k;i++)
#define for2(i,j,k) for(int i=j;i>=k;i--)
#define for3(i,j,k,l) for(int i=j;i<=k;i+=l)
#define lb lower_bound
#define ub upper_bound
#define sz(a) (int)a.size()
#define pii pair<int,int>
#define pli pair<long long,int>
#define gcd __gcd
#define lcm(x,y) x*y/__gcd(x,y)
const long long inf=1e18;
struct edg{
int u,v;
long long c,d;
}b[50009];
#define pil pair<int,long long>
vector<pil>a[209];
struct cus{
int u;
long long val;
bool operator < (const cus &p)const {
return val>p.val;
}
};
int p1[209],p2[209],rp1[209],rp2[209];
bool use[50009];
long long d[209][209];
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen("temp.INP","r",stdin);
    //freopen("temp.OUT","w",stdout);
    int n,m;
    cin>>n>>m;
    for1(i,1,m)cin>>b[i].u>>b[i].v>>b[i].c>>b[i].d;
    for1(i,1,n){
    for1(j,1,n){
    d[i][j]=inf;
    }
    d[i][i]=0;
    }
    for1(i,1,m){
    d[b[i].u][b[i].v]=min(d[b[i].u][b[i].v],b[i].c+1);
    }
    for1(i,1,n){
    for1(j,1,n){
    for1(k,1,n){
    d[j][k]=min(d[j][k],d[j][i]+d[i][k]);
    }
    }
    }
    auto dijkstra=[&](int s,int t){
    vector<bool>vis(n+1);
    vector<long long>d1(n+1);
    for1(i,1,n)d1[i]=inf;
    d1[s]=0;
    priority_queue<cus>t1;
    t1.push({s,0});
    while (!t1.empty()){
    auto u=t1.top();
    t1.pop();
    if (vis[u.u])continue;
    vis[u.u]=1;
    for (auto v:a[u.u]){
    long long val=u.val+v.se;
    if (val<d1[v.fi]){
    d1[v.fi]=val;
    t1.push({v.fi,d1[v.fi]});
    }
    }
    }
    return d1[t];
    };
    for1(i,1,n)a[i].clear();
    for1(i,1,m){
    if (d[1][b[i].u]+b[i].c+1==d[1][b[i].v]&&!p1[b[i].v]){
    p1[b[i].v]=b[i].u;
    use[i]=1;
    }
    if (d[n][b[i].u]+b[i].c+1==d[n][b[i].v]&&!p2[b[i].v]){
    p2[b[i].v]=b[i].u;
    use[i]=1;
    }
    if (d[b[i].v][n]+b[i].c+1==d[b[i].u][n]&&!rp1[b[i].u]){
    rp1[b[i].u]=b[i].v;
    use[i]=1;
    }
    if (d[b[i].v][1]+b[i].c+1==d[b[i].u][1]&&!rp2[b[i].u]){
    rp2[b[i].u]=b[i].v;
    use[i]=1;
    }
    }
    for1(i,1,n){
    for1(j,1,n){
    d[i][j]=inf;
    }
    d[i][i]=0;
    }
    for1(i,1,m){
    d[b[i].u][b[i].v]=min(d[b[i].u][b[i].v],b[i].c);
    }
    for1(i,1,n){
    for1(j,1,n){
    for1(k,1,n){
    d[j][k]=min(d[j][k],d[j][i]+d[i][k]);
    }
    }
    }
    long long ans=d[1][n]+d[n][1];
    auto invert=[&](int id){
    if (use[id]){
    for1(i,1,n)a[i].clear();
    swap(b[id].u,b[id].v);
    for1(i,1,m){
    a[b[i].u].pb({b[i].v,b[i].c});
    }
    swap(b[id].u,b[id].v);
    return b[id].d+dijkstra(1,n)+dijkstra(n,1);
    }
    return b[id].d+min(d[1][n],d[1][b[id].v]+b[id].c+d[b[id].u][n])+min(d[n][1],d[n][b[id].v]+b[id].c+d[b[id].u][1]);
    };
    for1(i,1,m){
    ans=min(ans,invert(i));
    }
    if (ans>=inf)ans=-1;
    cout<<ans;
}

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