#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e18;
const long long N = 2e5 + 5;
const long long mod = 1000000007;
string s;
long long n;
long long solve(long long ind) {
  long long ans = 0;
  for (long long i = ind; i < min(n, ind + 10); i++) {
    for (long long j = i + 1; j < min(n, ind + 10); j++) {
      long long diff = j - i;
      if (i + 2 * diff < n && s[i] == s[j] && s[i] == s[i + 2 * diff]) {
        ans = max(ans, n - (i + 2 * diff));
      }
    }
  }
  return ans;
}
void testCase() {
  cin >> s;
  n = s.size();
  long long ans = 0;
  for (long long i = 0; i < n; i++) {
    ans += solve(i);
  }
  cout << ans << "\n";
}
int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long t = 1;
  while (t--) testCase();
  return 0;
}
