#include <iostream>

 #include <cstdio>

 #include <cstring>

 #include <cstdlib>

 #include <algorithm>

 #include <queue>

 #include <vector>

 #include <cmath>

 #define min(a, b) ((a) < (b) ? (a) : (b))

 #define max(a, b) ((a) > (b) ? (a) : (b))

 #define abs(a) ((a) < 0 ? (-1 * (a)) : (a))

 inline void swap(long long &a, long long &b)

 {

     long long tmp = a;a = b;b = tmp;

 }

 inline void read(long long &x)

 {

     x = ;char ch = getchar(), c = ch;

     while(ch < '' || ch > '') c = ch, ch = getchar();

     while(ch <= '' && ch >= '') x = x *  + ch - '', ch = getchar();

     if(c == '-') x = -x;

 }

 const long long INF = 0x3f3f3f3f;

 const long long MAXN =  + ;

 const long long MOD = ;

 long long dp[MAXN][MAXN],n;

 char s[MAXN];

 int main()

 {

     while(scanf("%s", s + ) != EOF)

     {

         n = strlen(s + );

         memset(dp, , sizeof(dp));

         for(register long long i = ;i <= n;++ i) dp[i][i] = ;

         for(register long long k = ;k <= n;++ k)

             for(register long long i = ;i <= n;++ i)

             {

                 long long j = i + k - ;

                 if(j > n) break;

                 if(s[i] != s[j]) continue;

                 for(register long long k = i + ;k <= j;++ k)

                     if(s[i] == s[k]) dp[i][j] += dp[i + ][k - ] * dp[k][j] % MOD, dp[i][j] = dp[i][j] >= MOD ? dp[i][j] - MOD : dp[i][j];

             }

         printf("%lld\n", dp[][n]);

     }

     return ;

 }