1 /**************************************************************
2 Problem: 1001
3 User: 935671154
4 Language: C++
5 Result: Accepted
6 Time:8536 ms
7 Memory:104700 kb
8 ****************************************************************/ 9 10 #include <iostream>
11 #include <cctype>
12 #include <cstdio>
13 #include <vector>
14 #include <algorithm>
15 #include <cmath>
16 #include <queue>
17 using namespace std;
18 inline
void getd(
int &x){
19 char c = getchar();
20 bool minus =
0;
21 while(!isdigit(c) && c !=
‘-‘)c = getchar();
22 if(c ==
‘-‘)minus =
1, c = getchar();
23 x = c -
‘0‘;
24 while(isdigit(c = getchar()))x = x *
10 + c -
‘0‘;
25 if(minus)x = -x;
26 }
27 /*======================================================*/ 28 const int maxn =
2000003, INF =
0x3f3f3f3f;
29 #define pb push_back
30 struct edge{
31 int to, w;
32 edge(
int t,
int W):to(t), w(W){}
33 };
34 vector<edge> adj[maxn];
35 int N, M, To, dis[maxn] = {
0};
36 37 inline
bool init(){
38 int i, j, k, t, d;
39 getd(N), getd(M);
40 if(N ==
1){
41 int ans = INF;
42 for(i =
1;i < M;++i)
43 getd(t), ans = min(ans, t);
44 printf(
"%d\n", ans);
45 return 0;
46 }
47 if(M ==
1){
48 int ans = INF;
49 for(i =
1;i < N;++i)
50 getd(t), ans = min(ans, t);
51 printf(
"%d\n", ans);
52 return 0;
53 }
54 To = ((N-
1) * (M-
1) *
2) +
1;
55 //横向道路
56 d =
2 * M -
3;
57 for(i = k =
1;i < M;++i, k+=
2){
58 getd(t);
59 adj[
0].pb(edge(k, t));
60 }
61 for(i =
2;i < N;++i){
62 for(j =
1;j < M;++j, k+=
2){
63 getd(t);
64 adj[k].pb(edge(k-d, t));
65 adj[k-d].pb(edge(k, t));
66 }
67 }
68 for(j =
1, k = To-
2*(M-
2)-
1;j < M;++j, k+=
2){
69 getd(t);
70 adj[k].pb(edge(To, t));
71 }
72 //纵向道路
73 for(i =
1,k =
2;i < N;++i){
74 getd(t);
75 adj[k].pb(edge(To, t));
76 for(j =
2,k+=
2;j < M;++j,k+=
2){
77 getd(t);
78 adj[k].pb(edge(k-
3, t));
79 adj[k-
3].pb(edge(k, t));
80 }
81 getd(t);
82 adj[
0].pb(edge(k-
3, t));
83 }
84 //斜向道路
85 for(i =
1, k =
1;i < N;++i){
86 for(j =
1;j < M;++j, k +=
2){
87 getd(t);
88 adj[k].pb(edge(k+
1, t));
89 adj[k+
1].pb(edge(k, t));
90 }
91 }
92 for(i =
1;i <= To;++i)
93 dis[i] = INF;
94 return 1;
95 }
96 queue<
int> Q;
97 bool inQ[maxn] = {
1};
98 inline
void work(){
99 Q.push(
0);
100 int t;
101 vector<edge>::iterator it;
102 while(!Q.empty()){
103 t = Q.front();Q.pop();inQ[t] =
0;
104 for(it = adj[t].begin();it != adj[t].end();++it)
105 if(dis[t] + it->w < dis[it->to]){
106 dis[it->to] = dis[t] + it->w;
107 if(!inQ[it->to])
108 Q.push(it->to), inQ[it->to] =
1;
109 }
110 }
111 printf(
"%d\n", dis[To]);
112 }
113 114 int main(){
115 #if defined DEBUG
116 freopen(
"test",
"r", stdin);
117 #endif118 119 if(init())
120 work();
121 122 #if defined DEBUG
123 cout << endl << (
double)clock()/CLOCKS_PER_SEC << endl;
124 #endif125 return 0;
126 }
