file = "Задача_3__fz2g (1).txt"

with open(file, "r") as f:
    data = f.read()

sum_ = 0

counted = False
for i in range(1, len(data)):
    if data[i] == data[i - 1]:
        if counted:
            counted = False
            continue
        else:
            sum_ += int(data[i] + data[i - 1])
            counted = True
    else:
        if counted:
            counted = False

print(sum_)