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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void canhazfast() {ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

ll tri(int k) { return ll(k+1)*k/2; }

#define N 300032

char s[N];
int f[N];
pii pos[N];

/// 2c
ll calc(const char t[], int n, char c)
{
    ll res = 0;
    for (int i = 0; i < n; ++i) f[i+1] = f[i]+(t[i] == c ? +1 : -1);
    sort(f, f+n+1);
    for (int i = 0, j = 0; i <= n; i = j) {
        while (j <= n && f[j] == f[i]) ++j;
        res += tri(j-i-1);
    }
    return res;
}

int main()
{
    canhazfast();

    int n, p = 0, x = 0, y = 0;
    ll ans = 0;

    cin >> s;
    n = strlen(s);
    /// 3c
    for (int i = 0; i < n; ++i) {
        if (s[i] == 'a') ++x;
        else if (s[i] == 'b') ++y;
        else --x, --y;
        pos[i+1] = {x, y};
    }
    sort(pos, pos+n+1);
    for (int i = 0, j = 0; i <= n; i = j) {
        while (j <= n && pos[j] == pos[i]) ++j;
        ans += tri(j-i-1);
    }
    /// 2c
    while (p < n && s[p] == s[0]) ++p;
    for (int i = 0, j = p; p < n; p = j) {
        int last = i;
        while (j < n && (s[j] == s[i] || s[j] == s[p])) {
            if (s[j] != s[last]) last = j;
            ++j;
        }
        ans += calc(s+i, j-i, s[i]);
        brif(j == n);
        i = last;
    }
    /// 1c
    for (int i = 0, j = 0; i < n; i = j) {
        while (j < n && s[j] == s[i]) ++j;
        ans += tri(j-i);
    }
    cout << ans << '\n';

    return 0;
}