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#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define debug(...) {}
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);

	string s;
	cin >> s;
	int n = s.length();
	LL ans = 0;
	map<pair<int,int>,int> m = {{{0,0},1}};
	pair<int,int> p = {0,0};
	REP(i,n) {
		if (s.at(i) == 'a') {
			++p.first;
			++p.second;
		}
		else if (s.at(i) == 'b') {
			--p.first;
		}
		else {
			--p.second;
		}
		ans += m[p];
		++m[p];
	}
	REP(i,3) {
		char zak = 'a' + i;
		char fir = 'a';
		if (fir == zak) ++fir;
		REP(j,n) {
			map<int,int> m2;
			int val = 0;
			m2[0] = 1;
			int x = j;
			while (x < n && s.at(x) != zak) {
				if (s.at(x) == fir) ++val;
				else --val;
				ans += m2[val];
				++m2[val];
				++x;
			}
			j = x;
		}
	}
	REP(i,3) {
		char fir = 'a' + i;
		REP(j,n) {
			int x = j;
			while (x < n && s.at(x) == fir) {
				++x;
			}
			ans += (LL) (x - j + 1) * (x - j) / 2;
			j = x;
		}
	}
	cout << ans << '\n';	
}