#include<bits/stdc++.h>
using namespace std;
const long long MaxN = 1e5 + 5;
string s;
long long prefix[MaxN][30],ans=0,m;
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen("B2.inp","r"))
    {
        freopen("B2.inp","r",stdin);
        freopen("B2.out","w",stdout);
    }
    cin >> s;
    m=s.size();
    s=" " + s;
    for (long long i=1; i<=m; i++)
    {
        for (long long j=1; j<=26;j++)
        {
            prefix[i][j]=prefix[i-1][j];
            if(j==s[i]-'a'+1)
            {
                prefix[i][j]++;
            }
        }
    }
    for (long long len =1; len<=m/2; len++)
    {
        for (long long l=1; l+2*len-1<=m; l++)
        {
            bool check = true;
            for (long long i=1; i<=26; i++)
            {
                long long t_1=prefix[l+len-1][i]-prefix[l-1][i];
                long long t_2=prefix[l+2*len-1][i]-prefix[l+len-1][i];
                if(!((t_1>0&&t_2>0)||(t_1==0&&t_2==0)))
                {
                    check = false;
                }
            }
            if(check)
            {
                ans++;
            }
        }
    }
    cout << ans;
}