【模板】分层图

题目传送门

#include<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
#define INF 0x3f3f3f3f
using namespace std;
int dis[10000001],vis[10000001],head[10000001],n,m,k,N;
struct Node{
    int nxt,to,edge;
}a[10000001];
struct node{
    int id,Dis;
    friend bool operator < (node AA,node BB){
        if(AA.Dis==BB.Dis) return AA.id>BB.id;
        return AA.Dis>BB.Dis;
    }
};
int add(int U,int V,int VAL){
    a[++N].to=V;
    a[N].edge=VAL;
    a[N].nxt=head[U];
    head[U]=N;
    return 0;
}
int Min(int AAA,int BBB){
    return AAA<BBB ? AAA : BBB ;
}
inline int read(){
    int s=0,w=1;
    char ch=getchar();
    while(ch<'0'||ch>'9'){
        if(ch=='-') w=-1;
        ch=getchar();
    }
    while(ch>='0'&&ch<='9'){
        s=(s<<1)+(s<<3)+(ch^48);
        ch=getchar();
    }
    return s*w;
}
int dijiesitela(){
    memset(dis,INF,sizeof(dis));
    priority_queue<node> q;
    node useless;
    useless.id=1;
    useless.Dis=0;
    q.push(useless);
    dis[1]=0;
    while(!q.empty()){
        node u=q.top();
        q.pop();
        if(vis[u.id]==1) continue;
        vis[u.id]=1;
        for(int i=head[u.id];i;i=a[i].nxt){
            int v=a[i].to;
            if(vis[v]==0&&dis[u.id]+a[i].edge<dis[v]){
                dis[v]=dis[u.id]+a[i].edge;
                node vv;
                vv.id=v;
                vv.Dis=dis[v];
                q.push(vv);
            }
        }
    }
    int minn=INF;
    for(int i=0;i<=k;i++) minn=Min(minn,dis[n+i*n]);
    return minn;
}
int main(){
    n=read();
    m=read();
    k=read();
    for(int i=1;i<=m;i++){
        int X=read(),Y=read(),Z=read();
        add(X,Y,Z);
        add(Y,X,Z);
        for(int j=1;j<=k;j++){
            add(X+(j-1)*n,Y+j*n,Z/2);
            add(Y+(j-1)*n,X+j*n,Z/2);
            add(X+j*n,Y+j*n,Z);
            add(Y+j*n,X+j*n,Z);
        }
    }
    printf("%d",dijiesitela());
    return 0;
}

标签：node,AA,10000001,int,分层,id,模板,Dis
来源： https://www.cnblogs.com/latent-Lin/p/15526018.html