# hdu4632Palindrome subsequence

http://acm.hdu.edu.cn/showproblem.php?pid=4632

TLE了N次 原因居然是取模次数太多了。。！ 这数据卡的好紧 还是我写的太搓。。828ms挤过

s[i]==s[j] dp[i][j] = dp[i][j-1]+dp[i+1][j]+1;

else  dp[i][j] = dp[i][j-1]+d[[i+1][j]-dp[i+1][j-1];

 1 #include <iostream>
2 #include<cstdio>
3 #include<cstring>
4 #include<algorithm>
5 using namespace std;
6 #define mod 10007
7 char s[1010];
8 int dp[1010][1010],k;
9 int find(int i,int j)
10 {
11     if(dp[i][j])
12     return dp[i][j];
13     if(i==j)
14     {
15         dp[i][j] = 1;
16         return 1;
17     }
18     if(j-i==1)
19     {
20         if(s[i]==s[j])
21         {
22             dp[i][j] = 3;
23             return 3;
24         }
25         else
26         {
27             dp[i][j] = 2;
28             return 2;
29         }
30     }
31     if(s[i]==s[j])
32     return dp[i][j]=(find(i,j-1)+find(i+1,j)+1)%mod;
33     else
34     return dp[i][j]=(find(i,j-1)+find(i+1,j)-find(i+1,j-1)+mod)%mod;
35     return dp[i][j];
36 }
37 int main()
38 {
39     int i,j,t,kk=0;
40     scanf("%d",&t);
41     while(t--)
42     {
43         kk++;
44         memset(dp,0,sizeof(dp));
45         scanf("%s",s);
46         k = strlen(s);
47         int ans = find(0,k-1);
48         printf("Case %d: ",kk);
49         printf("%d\n",ans);
50     }
51     return 0;
52 }
View Code

posted @ 2013-08-14 14:06  _雨  阅读(252)  评论(0编辑  收藏  举报