UVA 10453 十七 Make Palindrome

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <algorithm>
 4 using namespace std;
 5 
 6 char str[1005];
 7 int dp[1005][1005],react[1005][1005];
 8 
 9 int dfs(int x,int y)
10 {
11     if(x>y)
12         return 0;
13     if(x==y)
14         printf("%c",str[x]);
15     else if(react[x][y]==0)
16     {
17         printf("%c",str[x]);
18         dfs(x+1,y-1);
19         printf("%c",str[y]);
20     }
21     else if(react[x][y]==1)
22     {
23         printf("%c",str[y]);
24         dfs(x,y-1);
25         printf("%C",str[y]);
26     }
27     else if(react[x][y]==2)
28     {
29         printf("%c",str[x]);
30         dfs(x+1,y);
31         printf("%c",str[x]);
32     }
33     return 0;
34 }
35 
36 int main()
37 {    
38     int n;
39     int i,j,k;
40     while(scanf("%s",str)!=EOF)
41     {
42         memset(dp,0,sizeof(dp));
43         memset(react,0,sizeof(react));
44 
45         n=strlen(str);
46         for(i=n-1;i>=0;i--)
47         {
48             for(j=i+1;j<n;j++)
49             {
50                 if(str[i]==str[j])
51                 {
52                     dp[i][j]=dp[i+1][j-1];
53                 }
54                 else
55                 {
56                     if(dp[i+1][j]>dp[i][j-1])
57                     {
58                         dp[i][j]=dp[i][j-1]+1;
59                         react[i][j]=1;
60                     }
61                     else
62                     {
63                         dp[i][j]=dp[i+1][j]+1;
64                         react[i][j]=2;
65                     }
66                 }
67             }
68         }
69 
70         printf("%d ",dp[0][n-1]);
71         dfs(0,n-1);
72         printf("\n");
73     }
74     return 0;
75 }