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#include <unordered_map>
#include <array>
#include <cstdio>

using namespace std;

template<> struct std::hash<pair<int,int>> {
	size_t operator()(pair<int,int> const& d) const
	{
		return hash<long long>{}(
			(1LL<<20)*(d.second+30000) +
			d.first+30000
		);
	}
};

int main() {
	unordered_map<pair<int,int>, int> count3;
	unordered_map<int, int> count2[3];
	char last = '\0';
	int count1 = 0;
	int counts[3] = {0};
	int counts_pairs[3][3] = {{0}};

	int c, inp = 0, diff;
	long long result = 0;
	while((c = getchar()) > 0){
		if((c & 0b11111100) == 0x60) {
			if (c != last) {
				result += 1LL*count1*(count1+1) / 2;
				count1 = 1;
				last = c;
			} else {
				++count1;
			}
			inp = c - 'a';
			for (int i = 0; i < 3; ++i)
				counts_pairs[inp][i] = 0;
			++counts[inp];
			for (int i = 0; i < 3; ++i)
				++counts_pairs[i][inp];
			count2[inp].clear();
			for (int i = 0; i < 3; ++i) {
				if (i != inp) {
					diff = counts_pairs[i][(i+2)%3] - counts_pairs[i][(i+1)%3];
					count2[i][diff] += 1;
					//printf("%d %d %d %d\n", inp, i, diff, count2[i][diff]); 
					result += count2[i][diff] - (diff == 0 ? 0 : 1);
				}
			}
			auto diffs = make_pair(counts[2]-counts[1], counts[1]-counts[0]);
			count3[diffs] += 1;
			result += count3[diffs] - (diffs.first == 0 && diffs.second == 0 ? 0 : 1);
		}
	}
	result += 1LL*count1*(count1+1) / 2;
	printf("%lld\n", result);
}