【NOI2018】归程

kruskal重构树

https://www.cnblogs.com/zwfymqz/p/9683523.html

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<queue>
using namespace std;
const int maxn=200004,maxm=400004;
int n,m,lastans,cnt=0,cnt1=0,head[maxn],fa[maxn],dep[maxn<<1],f[maxn<<1][20],vis[maxn],dis[maxn],head1[maxn<<1];
struct node{
    int to,next,w;
}e[maxm<<1],tr[maxn<<1];
struct heap{
    int u,w;
};
inline bool operator < (const heap &x,const heap &y){
    return x.w>y.w;
}
struct data{
    int u,v,w,hi;
}a[maxm];
inline bool operator < (const data &x ,const data &y){
    return x.hi>y.hi;
}
struct node1{
    int l,height;
}p[maxn<<1];
inline int find(int u){
    if(fa[u]==u) return fa[u];
    fa[u]=find(fa[u]);
    return fa[u];
}
inline void add(int u,int v,int w){
    e[cnt].next=head[u];e[cnt].to=v;e[cnt].w=w;head[u]=cnt++;
}
inline void add1(int u,int v){
    tr[cnt1].next=head1[u];tr[cnt1].to=v;head1[u]=cnt1++;
}
inline void dij(){
    memset(vis,0,sizeof(vis));
    memset(dis,0x3f,sizeof(dis));
    priority_queue<heap>q;
    dis[1]=0;
    q.push((heap){1,0});
    while(!q.empty()){
        heap x=q.top();q.pop();
        if(vis[x.u]) continue;vis[x.u]=1;
        for(int i=head[x.u];i!=-1;i=e[i].next){
            int v=e[i].to;
            if(vis[v]) continue;
            if(dis[v]>dis[x.u]+e[i].w) {
                dis[v]=dis[x.u]+e[i].w;
                q.push((heap){v,dis[v]});
            }
        }
    }
    for(int i=1;i<=n;i++) p[i].l=dis[i];
}
inline void dfs(int u,int father){
    dep[u]=dep[father]+1,f[u][0]=father;
    for(int i=1;i<=19;i++) f[u][i]=f[f[u][i-1]][i-1];
    for(int i=head1[u];i!=-1;i=tr[i].next){
        int v=tr[i].to;
        if(v!=father){
            dfs(v,u);
            p[u].l=min(p[u].l,p[v].l);
        }
    }
}
inline int query(int x,int y){
    for(int i=19;i>=0;i--){
        if(dep[x]-(1<<i)>0&&p[f[x][i]].height>y) x=f[x][i];
    }
    return p[x].l;
}
inline void kruskal(){
    memset(f,0,sizeof(f));
    int sum=n;
    for(int i=1;i<=(n<<1);i++) fa[i]=i;
    sort(a+1,a+m+1);
    for(int i=1;i<=m;i++){
        int u=a[i].u,v=a[i].v;
        int x=find(u),y=find(v);
        if(x!=y){
            add1(++sum,x);add1(sum,y);
            fa[x]=sum;fa[y]=sum;
            p[sum].height=a[i].hi;
        }
    }
    dfs(sum,0);
    int q,k,s;scanf("%d%d%d",&q,&k,&s);
    while(q--){
        int x,y;scanf("%d%d",&x,&y);
        x=(k*lastans+x-1)%n+1,y=(k*lastans+y)%(s+1);
        lastans=query(x,y);
        printf("%d
",lastans);
    }
}
int main(){
    int T;scanf("%d",&T);
    while(T--){
        lastans=0;cnt=cnt1=0;
        memset(head,-1,sizeof(head));
        memset(head1,-1,sizeof(head1));
        memset(e,0,sizeof(e));
        memset(tr,0,sizeof(tr));
        memset(a,0,sizeof(a));
        memset(p,0,sizeof(p));
        memset(dep,0,sizeof(dep));
        memset(f,0,sizeof(f));
        
        scanf("%d%d",&n,&m);
        for(int i=1;i<=m;i++){
            scanf("%d%d%d%d",&a[i].u,&a[i].v,&a[i].w,&a[i].hi);
            add(a[i].u,a[i].v,a[i].w);add(a[i].v,a[i].u,a[i].w);
        }
        for(int i=n+1;i<=(n<<1);i++) p[i].l=0x3f3f3f3f;
        dij();
        kruskal();
    }
    return 0;
}