#import<bits/stdc++.h>
int n,j,k,re;char s[501];main(){std::cin>>n>>s;for(re=0,n++;--n;)for(j=n;j--;)for(k=0;k<n-j&&s[j+k]==s[n-k-1];re += k++==n-j-1);printf("%d\n",re);}