#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 5;
bool check(string f) {
  int n = f.size();
  for (int i = 0; i < 9; ++i) {
    for (int j = 1; j <= 9; ++j) {
      if (i < n && i + j < n && i + 2 * j < n) {
        if (f[i] == f[i + j] && f[i] == f[i + 2 * j]) return true;
      }
    }
  }
  return false;
}
int main(int argc, char const *argv[]) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  string s;
  cin >> s;
  int n = s.size();
  ll ans = 0;
  for (int i = 0; i < n; ++i) {
    string f = "";
    for (int j = i; j < n; ++j) {
      f += s[j];
      if (check(f)) {
        ans += (n - j);
        break;
      }
    }
  }
  cout << ans;
  return 0;
}
