poj 3280 Cheapest Palindrome
http://poj.org/problem?id=3280
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
1 #include <cstdio> 2 #include <cstring> 3 #include <algorithm> 4 #define maxn 2000010 5 using namespace std; 6 7 char str[maxn],ch; 8 int a[maxn]; 9 int n,m; 10 int dp[2020][2020]; 11 12 int main() 13 { 14 while(scanf("%d%d",&n,&m)!=EOF) 15 { 16 getchar(); 17 scanf("%s",str); 18 getchar(); 19 int x,y; 20 for(int i=0; i<n; i++) 21 { 22 scanf("%c %d%d",&ch,&x,&y); 23 a[ch-'a']=min(x,y); 24 getchar(); 25 } 26 for(int i=m-1; i>=0; i--) 27 { 28 for(int j=i+1; j<m; j++) 29 { 30 if(str[i]==str[j]) dp[i][j]=dp[i+1][j-1]; 31 else dp[i][j]=min(dp[i+1][j]+a[str[i]-'a'],dp[i][j-1]+a[str[j]-'a']); 32 } 33 } 34 printf("%d\n",dp[0][m-1]); 35 } 36 return 0; 37 }