Python技术问询：如何检测循环中连续两次输入是否相同，且连续输入0时终止程序

Hey there! You don't need an extra loop to add this feature—all you need is a single variable to track the previous input value. Here's how to implement it:

Key Ideas #

• Add a variable like previous_number to store the last integer the user entered. Initialize it to a non-zero value (like None) so the first input of 0 doesn't accidentally trigger the termination.
• After each new input, check if both the current input and the previous one are 0. If yes, print your termination message and exit the loop immediately.
• Even if you haven't collected all the requested numbers yet, the program should stop as soon as two consecutive zeros are detected.

Modified Full Code #

amount_of_integers = int(input("How many numbers do you want to count together: "))
total_sum = 0
repeat_counter = 1
previous_number = None  # Tracks the last input, starts as None to avoid false triggers

while repeat_counter <= amount_of_integers:
    current_num = int(input(f"Enter the value of the number {repeat_counter}: "))
    
    # Check for two consecutive zeros
    if previous_number == 0 and current_num == 0:
        print("\nTwo consecutive zero's detected. The program ends.")
        break
    
    total_sum += current_num
    previous_number = current_num  # Update the previous number to current input
    repeat_counter += 1
else:
    # This block runs only if the loop finishes normally (no break triggered)
    print()
    print("The sum of counted numbers is", total_sum)

Breakdown of Changes #

1. previous_number Variable: This keeps track of the last input. Starting with None ensures that if the first input is 0, there's no "previous" 0 to trigger the termination.
2. Consecutive Zero Check: Right after getting the current input, we check if both it and the previous input are 0. If so, we print the message and use break to exit the loop immediately.
3. while Loop else Block: This is a handy Python feature—this block runs only when the loop completes all iterations (i.e., we collected all requested numbers without hitting the consecutive zero condition). It prints the total sum in that case.
4. Renamed sum to total_sum: sum is a built-in Python function, so using it as a variable name can cause unexpected issues. Renaming it avoids that conflict.

Test Examples #

Termination Triggered #

How many numbers do you want to count together: 5
Enter the value of the number 1: 1
Enter the value of the number 2: 0
Enter the value of the number 3: 0

Two consecutive zero's detected. The program ends.

Normal Completion #

How many numbers do you want to count together: 3
Enter the value of the number 1: 2
Enter the value of the number 2: 4
Enter the value of the number 3: 6

The sum of counted numbers is 12

内容的提问来源于stack exchange，提问作者lute