hdu 1208 记忆化搜索

 1 #include<cstdio>
 2 #include<iostream>
 3 #include<algorithm>
 4 #include<cstring>
 5 #include<cmath>
 6 #include<queue>
 7 #include<map>
 8 using namespace std;
 9 #define MOD 1000000007
10 const int INF=0x3f3f3f3f;
11 const double eps=1e-5;
12 #define cl(a) memset(a,0,sizeof(a))
13 #define ts printf("*****\n");
14 const int MAXN=1005;
15 int n,m,tt;
16 long long dp[40][40];
17 char s[40][40];
18 int a[40][40];
19 int d[2][2]={1,0,0,1};
20 long long dfs(int x,int y)
21 {
22     if(dp[x][y]||!a[x][y])    return dp[x][y];
23     for(int i=0;i<2;i++)
24     {
25         int nx=x+d[i][0]*a[x][y];
26         int ny=y+d[i][1]*a[x][y];
27         if(nx>=0&&nx<n&&ny>=0&&ny<n)
28         {
29             dp[x][y]+=dfs(nx,ny);
30         }
31     }
32     return dp[x][y];
33 }
34 int main()
35 {
36     int i,j,k;
37     #ifndef ONLINE_JUDGE
38     freopen("1.in","r",stdin);
39     #endif
40     while(scanf("%d",&n)!=EOF&&n>0)
41     {
42         for(i=0;i<n;i++)
43         {
44             scanf("%s",s[i]);
45             for(j=0;j<n;j++)
46             {
47                 a[i][j]=s[i][j]-‘0‘;
48             }
49         }
50         memset(dp,0,sizeof(dp));
51         dp[n-1][n-1]=1;
52         printf("%I64d\n",dfs(0,0));
53     }
54 }