def req_input_length(trgt):
    """
    Function to calculate the minimum required input length from the target.
    Req. Input Length = No. of unique chars in target + No. of repeats in repeated chars (excluding the first one)
    """
    reqLen = len(trgt)
    lastChar = trgt[0]
    for i in range(1, len(trgt)):
        if trgt[i] != lastChar:
            lastChar = trgt[i]
        else:
            reqLen = reqLen + 1
    return reqLen