Question:
Give you a string and ask you the maximum number of ECHO strings contained in this string
Practice:
Dp [l] [r]: The number of input strings contained in the string l to r.
If l = r: dp [l] [r] = dps (l + 1, R-1) + 1 + (dps (l + 1, r) + dps (l, r-1)-dps (l + 1, R-1 ));
Otherwise: dp [l] [r] = (dps (l + 1, r) + dps (l, R-1)-dps (l + 1, R-1 ));
#include<stdio.h>#include<string.h>#include<iostream>using namespace std;#define P 10007char str[1001];int dp[1001][1001];int dps(int l,int r){ if(dp[l][r]!=-1)return dp[l][r]; if(l==r) { dp[l][r]=1; return 1; } if(l+1==r) { if(str[l]==str[r])dp[l][r]=3; else dp[l][r]=2; return dp[l][r]; } dp[l][r]=0; if(str[l]==str[r])dp[l][r]=dps(l+1,r-1)+1; dp[l][r]+=(dps(l+1,r)+dps(l,r-1)-dps(l+1,r-1)); dp[l][r]=dp[l][r]%P; if(dp[l][r]<0)dp[l][r]+=P; return dp[l][r];}int main(){ int T; scanf("%d%*c",&T); int t=T; while(T--) { gets(str); int n; n=strlen(str); int i,j; for(i=0;i<n;i++) { for(j=0;j<n;j++) { dp[i][j]=-1; } } printf("Case %d: %d\n",t-T,dps(0,n-1)); } return 0;}