#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")

using namespace std;
typedef long double ld;
typedef long long int ll;
typedef unsigned long long int ull;
typedef vector<int> vi;
typedef vector<char> vc;
typedef vector<bool> vb;
typedef vector<double> vd;
typedef vector<string> vs;
typedef vector<ll> vll;
typedef vector<pair<int, int> > vpii;
typedef vector<vector<int> > vvi;
typedef vector<vector<char> > vvc;
typedef vector<vector<string> > vvs;
typedef vector<vector<ll> > vvll;
typedef vector<vector<bool> > vvb;

#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define rrep(i, n) for (int i = 1; i <= int(n); ++i)
#define irep(it, stl) for (auto it = stl.begin(); it != stl.end(); it++)
#define drep(i, n) for (int i = int(n)-1; i >= 0; --i)

#define MES(a) MES2 a
#define MES2(a0,a1,a2,a3,a4,x,...) x
#define mes_1(x1) cout<<x1<<endl
#define mes_2(x1,x2) cout<<x1<<" "<<x2<<endl
#define mes_3(x1,x2,x3) cout<<x1<<" "<<x2<<" "<<x3<<endl
#define mes_4(x1,x2,x3,x4) cout<<x1<<" "<<x2<<" "<<x3<<" "<<x4<<endl
#define mes_5(x1,x2,x3,x4,x5) cout<<x1<<" "<<x2<<" "<<x3<<" "<<x4<<" "<<x5<<endl
#define mes(...) CHOOSE((__VA_ARGS__,mes_5,mes_4,mes_3,mes_2,mes_1,~))(__VA_ARGS__)

#define CHOOSE(a) CHOOSE2 a
#define CHOOSE2(a0,a1,a2,a3,a4,x,...) x
#define debug_1(x1) cout<<#x1<<": "<<x1<<endl
#define debug_2(x1,x2) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<endl
#define debug_3(x1,x2,x3) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<endl
#define debug_4(x1,x2,x3,x4) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<", "#x4<<": "<<x4<<endl
#define debug_5(x1,x2,x3,x4,x5) cout<<#x1<<": "<<x1<<", "#x2<<": "<<x2<<", "#x3<<": "<<x3<<", "#x4<<": "<<x4<<", "#x5<<": "<<x5<<endl
#define debug(...) CHOOSE((__VA_ARGS__,debug_5,debug_4,debug_3,debug_2,debug_1,~))(__VA_ARGS__)

#define ynmes(a) (a) ? mes("Yes") : mes("No")
#define YNmes(a) (a) ? mes("YES") : mes("NO")
#define re0 return 0
#define mp(p, q) make_pair(p, q)
#define pb(n) push_back(n)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define Sort(a) sort(a.begin(), a.end())
#define rSort(a) sort(a.rbegin(), a.rend())
#define Rev(a) reverse(a.begin(), a.end())
#define MATHPI acos(-1)
#define itn int;
int dx[8] = { 1, 0, -1, 0, 1, -1, -1, 1 };
int dy[8] = { 0, 1, 0, -1, 1, 1, -1, -1 };
template <class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template <class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
struct io { io() { ios::sync_with_stdio(false); cin.tie(0); } };
const int INF = INT_MAX;
const ll LLINF = 1LL << 60;
const ll MOD = 1000000007;
const double EPS = 1e-9;

ll fact_mod(ll n, ll mod) {
    ll f = 1; for (ll i = 2; i <= n; i++) f = f * (i % mod) % mod;
    return f;
}

ll modpow(ll x, ll n, ll mod) {
    if(n == 0) return 1;
    ll res = modpow((x * x) % mod, n / 2 , mod);
    if(n & 1) res = (res * x) % mod;
    return res;
}

ll modncr(ll n, ll r, ll mod) {
    if(r > n-r) r = n-r;
    if(r == 0) return 1;
    ll a = 1;
    rep(i, r) a = a * ((n-i) % mod) % mod;
    ll b = modpow(fact_mod(r, mod), mod-2, mod);
    return (a % mod) * (b % mod) % mod;
}


signed main() {
	string s;
	cin >> s;
	ll r = 0;
	ll n = s.size();
	stack <char> stk;
	
	rep(i, n) {
		if (i && s[i] == s[i-1]) stk.push(s[i]);
	}
	
	if (stk.empty()) {
		mes(0);
		re0;
	}
	
	ll tmp = 0;
	drep(i, n) {
		if (stk.empty()) break;
		
		if (i && s[i] == s[i-1]) {
			stk.pop();
			r += tmp;
			tmp = 0;
			if (!stk.empty() && stk.top() != s[i-1]) tmp += n-i;
		} else {
			if (stk.top() != s[i]) tmp++;
		}
	}
	
	mes(r);
	
	
	
	
	
	
}

#include<bits/stdc++.h>
#define ll long long
#define f first
#define s second
#define pb push_back
using namespace std;
string s;
ll ans,raod[200];
int main(){
    ios::sync_with_stdio(false);
    cin >> s;
    
    for(int i=(int)s.size() - 1; i>=1; i--){
        if(s[i] == s[i - 1]){
            ans += (int)s.size() - i - 1 - raod[s[i] - 'a'];
            for(int j=0; j<26; j++)
                raod[j] = 0;
            raod[s[i] - 'a'] = (int)s.size() - i;
        }
        else {
            raod[s[i] - 'a']++;
        }
    }
    
    cout << ans << '\n';
    
    
    
    return 0;
}
