计算数组中后续组的数量

def count_consecutive_groups(arr):
    if len(arr) < 2:
        return 0

    left, right = 0, 1
    count = 1

    for right in range(2, len(arr)):
        if arr[right] == arr[right - 1]:
            count += 1
        else:
            left = right
            count = 1

    return count + left + 1