#include <bits/stdc++.h>
using namespace std;
int n;
string s;
string xxxxxx;
bool czy(int left, int right) {
  for (int x = left; x <= right; x++) {
    for (int k = 1; k <= 15; k++) {
      if (x + 2 * k > right) break;
      if (s[x] == s[x + k] && s[x] == s[x + 2 * k]) return true;
    }
  }
  return false;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> xxxxxx;
  s = '0' + xxxxxx;
  n = s.length() - 1;
  long long int res = 0;
  for (int left = 1; left <= n; left++) {
    int right = left + 2;
    if (right > n) continue;
    bool xd = false;
    while (right <= n) {
      bool ok = czy(left, right);
      if (ok) {
        xd = true;
        break;
      } else
        right++;
    }
    if (xd == false) continue;
    res += n - right + 1;
  }
  cout << res << endl;
  return 0;
}
