#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main(){
    string S;
    cin >> S;
    int l = S.length();
    vector<int> dp(l+1,0);
    if(S[0] == S[1] && S[2] != S[1]){
        dp[3] = 1;
    }
    ll next = 0;
    for(int i=4;i<=l;i++){
        string re = S.substr(0,i-2);
        char x = S[i-2];
        ll up = count(re.begin(),re.end(),x);
        if(x == S[i-1]){
            dp[i]+=up;   
        }else{
            dp[i]+=up+next;
            next=0;
        }
        char y = S[i-1];
        string re2 = S.substr(0,i-1);
        ll down = count(re2.begin(),re2.end(),y);
        if(down<2){
            dp[i] += dp[i-1];
        }else{
            ll mi = down * (down-1)/2;
            dp[i] += dp[i-1]-mi;
            next = mi;
        }
    }
    for(int i=1;i<=l;i++){
        dp[i] += dp[i-1];
    }
    cout << dp[l] << endl;
}