#include <bits/stdc++.h>
using namespace std;
string s;
bool judge(int l, int r) {
  for (int i = l; i <= r - 2; i++)
    for (int k = 1; k <= 3 && i + 2 * k <= r; k++)
      if (s[i] == s[i + k] && s[i] == s[i + 2 * k]) return 1;
  return 0;
}
int main() {
  cin >> s;
  int n = s.size();
  long long res = 0;
  if (n >= 9) res = (long long)(n - 7) * (n - 8) / 2;
  for (int i = 0; i < n; i++)
    for (int j = 2; j < 8 && i + j < n; j++)
      if (judge(i, i + j)) res = (res + 1);
  printf("%lld\n", res);
}
