在遞回中只應用一次條件

我只想在遞回中應用一次條件。我的資料結構如下

stages = {"stage_1": False, "stage_2":False, "stage_3":False,"state_4": False}

我想從中隨機選擇任何階段并將狀態更改為 True。但是當真實階段的總數為 3 時，我想將 True 階段隨機更改為 False。但只有一次。然后它應該繼續將階段變為 True。當所有 4 個階段都為真時。遞回程序停止。我怎樣才能做到這一點 ？我已經嘗試了以下代碼。但它并不完整。

def process(stages):
    all_stages = [stage for stage, status in stages.items() if status == False]
    if len(all_stages) !=0:
        print(all_stages)
        select_ = random.choice(all_stages)
        print("\tselected stage: ",select_)
        
        stages[select_] = True
        process(stages)
    else:
        print("Done")
        print(stages)

process(stages)

這在不添加額外條件的情況下有效。我已經嘗試過以下一種。但這不起作用

def process(stages):
    all_stages = [stage for stage, status in stages.items() if status == False]
    if len(all_stages) !=0:
        print(all_stages)
        select_ = random.choice(all_stages)
        print("\tselected stage: ",select_)
        
        stages[select_] = True

        if len(all_stages) == 1:
            select_ = random.choice([stage for stage, status in stages.items() if status == True])
            stages[select_] = False
        process(stages)
    else:
        print("Done")
        print(stages)

process(stages)

uj5u.com熱心網友回復：

代碼是來自@NoBlockhit 的建議

stages = {"stage_1": False, "stage_2":False, "stage_3":False,"state_4": False}

status = True
def process(stages):
    global status
    print(status)
    all_stages = [stage for stage, status in stages.items() if status == False]
    if len(all_stages) !=0:
        print(all_stages)
        select_ = random.choice(all_stages)
        print("\tselected stage: ",select_)
        
        stages[select_] = True

        if status:
            if len(all_stages) == 1:
                select_ = random.choice([stage for stage, status in stages.items() if status == True])
                stages[select_] = False
                status = False
        process(stages)
    else:
        print("Done")
        print(stages)

process(stages)

uj5u.com熱心網友回復：

與許多遞回問題一樣，在函式呼叫中添加狀態會對您有很大幫助。

考慮對其進行內部呼叫process_internal()將獲得遞回的當前狀態，無論是階段 0 (False -> True)、階段 1 (True -> False) 還是階段 2 (False -> True)。

import random

def flip_random_state(stages, relevant_bool_val):
    [print(f"Stage: {key} with status {value}") for key, value in stages.items()]
    relevant_stages = [stage for stage, status in stages.items() if status == relevant_bool_val]
    selected_stage = random.choice(relevant_stages)
    print(f"\tSelected stage: {selected_stage}\n")
    stages[selected_stage] = not stages[selected_stage]
    return stages

def count_stages_with_status(stages, input_status):
    return len([stage for stage, status in stages.items() if status == input_status])

def process_internal(stages, state):
    print(f"State: {state}")
    if state == 2 and count_stages_with_status(stages, True) == 4:
        print("Done")
        print(stages)
        return
    
    if state == 0 or state == 2:
        relevant_bool_val = False
    else:
        relevant_bool_val = True

    if state == 1 and count_stages_with_status(stages, False) == 4:
        state = 2
        return process_internal(stages, state)
    
    if state == 0 and count_stages_with_status(stages, True) == 3:
        state = 1
        return process_internal(stages, state)

    stages = flip_random_state(stages, relevant_bool_val)

    return process_internal(stages, state)

def process(stages):
    return process_internal(stages, 0)

stages = {"stage_1": False, "stage_2": False, "stage_3": False,"state_4": False}
process(stages)

uj5u.com熱心網友回復：

您可以添加一個全域變數作為獲取的標志，無論您是否已經將一個設定回 False，或者添加一個可選引數，如 returnedToFalse=False 并在您最終將其設定為 false 時將其設定為 true。

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