poj3280 区间dp

 1 //Accepted    15880 KB    250 ms
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <iostream>
 5 using namespace std;
 6 const int imax_n = 2005;
 7 const int imax_m = 27;
 8 const int inf = 100000000;
 9 int dp[imax_n][imax_n];
10 int addcost[imax_m];
11 int deletecost[imax_m];
12 int n;
13 int m;
14 char s[imax_n];
15 int min(int a,int b)
16 {
17     return a<b?a:b;
18 }
19 void Dp()
20 {
21     memset(dp,0,sizeof(dp));
22     //for (int i=1;i<=n;i++)
23     //dp[i][i]=0;
24     for (int l=2;l<=n;l++)
25     {
26         for (int i=1;i<=n;i++)
27         {
28             int j=i+l-1;
29             dp[i][j]=inf;
30             if (s[i-1]==s[j-1]) dp[i][j]=dp[i+1][j-1];
31             dp[i][j]=min(dp[i][j],dp[i+1][j]+addcost[s[i-1]-‘a‘]);
32             dp[i][j]=min(dp[i][j],dp[i+1][j]+deletecost[s[i-1]-‘a‘]);
33             dp[i][j]=min(dp[i][j],dp[i][j-1]+addcost[s[j-1]-‘a‘]);
34             dp[i][j]=min(dp[i][j],dp[i][j-1]+deletecost[s[j-1]-‘a‘]);
35         }
36     }
37     printf("%d\n",dp[1][n]);
38 }
39 int main()
40 {
41     //while (scanf("%d%d",&m,&n)!=EOF)
42     {
43         scanf("%d%d",&m,&n);
44         scanf("%s",s);
45         char ss[5];
46         memset(addcost,0,sizeof(addcost));
47         memset(deletecost,0,sizeof(deletecost));
48         for (int i=1;i<=m;i++)
49         {
50             scanf("%s",ss);
51             scanf("%d%d",&addcost[ss[0]-‘a‘],&deletecost[ss[0]-‘a‘]);
52         }
53         Dp();
54     }
55     return 0;
56 }