#include <bits/stdc++.h>
using namespace std;
inline int read() {
  int v = 0, c = 1;
  char ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') c = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    v = v * 10 + ch - 48;
    ch = getchar();
  }
  return v * c;
}
const int N = 3e5 + 3;
int n, r;
long long ans;
char s[N];
int main() {
  scanf("%s", s + 1);
  n = strlen(s + 1);
  r = n + 1;
  for (int i = n - 1; i >= 1; --i) {
    r = min(r, i + 9);
    for (int k = 1; i + 2 * k <= r; ++k) {
      if (s[i] == s[i + k] && s[i] == s[i + k + k]) {
        r = min(r, i + k + k);
        break;
      }
    }
    ans += n - r + 1;
  }
  cout << ans;
  return 0;
}
