BZOJ 2007 海拔

 1 #include<algorithm>
 2 #include<cstdio>
 3 #include<cmath>
 4 #include<cstring>
 5 #include<iostream>
 6 #include<queue>
 7 using namespace std;
 8 int first[250005],next[2000005],go[2000005],tot,val[2000005];
 9 int dis[250005],vis[250005],S,T,n;
10 int read(){
11     char ch=getchar();int t=0,f=1;
12     while (ch<‘0‘||ch>‘9‘){if (ch==‘-‘) f=-1;ch=getchar();}
13     while (‘0‘<=ch&&ch<=‘9‘){t=t*10+ch-‘0‘;ch=getchar();}
14     return t*f;
15 }
16 void insert(int x,int y,int z){
17     tot++;
18     go[tot]=y;
19     next[tot]=first[x];
20     first[x]=tot;
21     val[tot]=z;
22 }
23 void add(int x,int y,int z){
24     insert(x,y,z);
25 }
26 int id(int x,int y){
27     if (x==0||y==n+1) return T;
28     if (x==n+1||y==0) return S;
29     return (x-1)*n+y;
30 }
31 void dijkstra(){
32     memset(dis,127/3,sizeof dis);
33     priority_queue< pair<int,int> ,vector< pair<int,int> > ,greater<pair<int,int> > > Q;
34     dis[S]=0;
35     Q.push(make_pair(0,S));
36     while (!Q.empty()){
37         int now=Q.top().second;Q.pop();
38         if (vis[now]) continue;
39         vis[now]=1;
40         for (int i=first[now];i;i=next[i]){
41             int pur=go[i];
42             if (dis[pur]>dis[now]+val[i]){
43                 dis[pur]=dis[now]+val[i];
44                 Q.push(make_pair(dis[pur],pur));
45             }
46         }
47     }
48 }
49 int main(){
50     n=read();
51     S=0,T=n*n+1;
52     for (int i=1;i<=n+1;i++)
53      for (int j=1;j<=n;j++)
54       add(id(i,j),id(i-1,j),read());
55     for (int i=1;i<=n;i++)
56      for (int j=1;j<=n+1;j++)
57       add(id(i,j-1),id(i,j),read()); 
58     for (int i=1;i<=n+1;i++)
59      for (int j=1;j<=n;j++)
60       add(id(i-1,j),id(i,j),read()); 
61     for (int i=1;i<=n;i++)
62      for (int j=1;j<=n+1;j++)
63       add(id(i,j),id(i,j-1),read());
64     dijkstra();  
65     printf("%d\n",dis[T]);
66 }