from collections import Counter

def remove_from_matrice(matrice, letter):
    if letter in matrice:
        if matrice[letter] == 1:
            matrice.pop(letter)
            return
        matrice[letter] -= 1
        return
    matrice[letter] = -1

def add_to_matrice(matrice, letter):
    if letter in matrice:
        if matrice[letter] == -1:
            matrice.pop(letter)
            return
        matrice[letter] += 1
        return
    matrice[letter] = 1

def index_of_anagrams(w, s):
    output = []
    matrice = dict(Counter(w))
    word_length = len(w)
    for i in range(word_length):
        matrice.setdefault(s[i], 0)
        remove_from_matrice(matrice, s[i])
    if len(matrice) == 0:
        output.append(0)
    for i in range(word_length, len(s)):
        remove_from_matrice(matrice, s[i])
        add_to_matrice(matrice, s[i - word_length])
        if len(matrice) == 0:
            output.append(i - word_length + 1)
    return output

# w, s = 'ab', 'abxaba'
w, s = 'hor', 'abhrorhoxhraohrox'
print(index_of_anagrams(w, s))