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

int T[3002][3];
string s;
	
bool sprawdz (int p, int k) {
	int l = -1;
	bool u = true;
	
	for (int i=0; i<3; ++i) {
		const int r = T[k][i]-T[p-1][i];
		if (r==0) continue;
		if (l==-1) l = r;
		if (l!=r) u = false;
	}
	return u;
}

int main () {
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin>>s;
	const int dl = s.size();
	if (dl>3000) return 0;
	for (int i=1; i<=dl; ++i) {
		if (s[i-1]=='a') T[i][0] = T[i-1][0]+1;
		else T[i][0] = T[i-1][0];
		
		if (s[i-1]=='b') T[i][1] = T[i-1][1]+1;
		else T[i][1] = T[i-1][1];
		
		if (s[i-1]=='c') T[i][2] = T[i-1][2]+1;
		else T[i][2] = T[i-1][2];
	}
	int cn=0;
	for (int i=1; i<=dl; ++i) {
		for (int j=i; j<=dl; ++j) {
			if (sprawdz(i, j))
				cn++;
		}
	}
	cout<<cn;
}