#include <bits/stdc++.h>
using namespace std;
int get() {
  char ch;
  while (ch = getchar(), (ch < '0' || ch > '9') && ch != '-')
    ;
  if (ch == '-') {
    int s = 0;
    while (ch = getchar(), ch >= '0' && ch <= '9') s = s * 10 + ch - '0';
    return s;
  }
  int s = ch - '0';
  while (ch = getchar(), ch >= '0' && ch <= '9') s = s * 10 + ch - '0';
  return s;
}
const int N = 3e5 + 5;
const int mo1 = 998244353;
const int mo2 = 1e9 + 7;
int n;
char s[N];
int lef[N];
int main() {
  scanf("%s", s + 1);
  n = strlen(s + 1);
  for (int i = 1; i <= n; i++) lef[i] = n + 1;
  long long ans = 0;
  for (int i = 1; i <= n; i++) {
    lef[i] = -1;
    if (i > 1) lef[i] = lef[i - 1];
    for (int x = i - 2; x >= max(1, lef[i]); x -= 2)
      if (s[x] == s[i] && s[x] == s[(x + i) / 2]) {
        lef[i] = x;
        break;
      }
    if (lef[i] != -1 && lef[i] <= i) ans = ans + lef[i];
  }
  cout << ans << endl;
  return 0;
}
