Denis & mdash; A novice programmer, and he dreams of a new powerful smartphone for work and entertainment. He decided that he would save 20% of his monthly salary for this purchase.
rnWrite a program that will help Denis calculate how much time he will need to accumulate the necessary amount. The program should request two values for the user: Denis's monthly salary and the full cost of a smartphone.
rn& nbsp;
rn in the first line the one-number is introduced & mdash; The size of the monthly salary.
In the second line, one number of & mdash is introduced in the second line; Full cost of a smartphone.
line & mdash; The number of months or or years that will be required to accumulate the right amount.
50000
25000
Access will take: 3 months
In the Python programming language, the while loop construction can have an optional else block. This block is executed only when the loop completes in its natural way, that is, when its condition becomes false, and not as a result of a forced interruption using the break operator.
Syntax:
EN
RU
EN
RU
while condition:
# the body of the loop
# ...the code that runs on each iteration...
else:
# else block
# ...the code that is executed if the loop ended without a break...
You can think of the else block as a "plan B": it is triggered if the main goal within the loop (which is usually completed through a break) has not been achieved.
Consider a classic problem where we search for a number in a list. If a number is found, we immediately break the loop using break. If we have checked all the elements and still haven't found what we are looking for, the else block is executed.
numbers = [1, 2, 3, 4, 5]
target = 8 # Let's try to find a number that is not in the list.
index = 0
while index < len(numbers):
if numbers[index] == target:
print(f"Success! {target} found at {index}.")
break # Goal reached, exit the loop
index += 1
else:
# This block will be executed because break was not called
print(f"The search is completed. {target} not found in the list.")
How it works:
whileloop is executed as long as the index < len(numbers) condition is true.target).break statement. The else block is ignored in this case.break has never worked. The index < len(numbers) condition becomes false, and then the else block is executed, reporting a failed search.A useful tip: Using while...else helps to avoid "flagged" variables. Without this block, the code would look like this:
# Alternative version with "flag"
numbers = [1, 2, 3, 4, 5]
target = 8
found = False # Flag variable
index = 0
while index < len(numbers):
if numbers[index] == target:
found = True
break
index += 1
if found:
print(f"Success! {target} found.")
else:
print(f"Search completed. {target} not found in the list.")
As you can see, the while...else construction makes the code cleaner, more concise, and more "Pythonic", eliminating the need to manually control the flag.
break is missingIf there is no break operator in the body of the while loop, then the else block will always be executed after the loop ends.
count = 0
while count < 3:
print(f"Iteration number {count}")
count += 1
else:
print("The loop ended naturally, so the else block is executed.")
Here, the while loop runs until count is less than 3. As soon as count becomes 3, the loop condition becomes false, and control is transferred to the else block.
continue? The continue operator does not interrupt the loop, but only ends the current iteration ahead of schedule. It does not affect the execution of the else block in any way.while condition is initially false, the loop body will not be executed even once. However, the else block will still run, since the loop ended "normally" (it was not interrupted via break).value = 10
while value < 5: # The condition is immediately false
print("This text will never be printed")
else:
print("The cycle didn't even start, but it ended normally, so else worked.")
for loops! The same logic applies to for...else loops. The else block after for is executed if the cycle has passed through all the elements and has not been interrupted using break.The while...else construction is a powerful and elegant Python tool. It is ideal for situations where you need to perform an action only if the loop has completed its work completely without being interrupted. This is especially useful in search algorithms, condition checking, or when working with data streams, where break signals a special event, and else indicates a regular termination without any.
# Запрашиваем у пользователя исходные данные
salary = float(input())
smartphone_cost = float(input())
# Проверяем, может ли Денис в принципе копить
if salary <= 0:
print("При такой зарплате Денис никогда не сможет накопить на смартфон.")
else:
# Рассчитываем, сколько Денис откладывает каждый месяц
monthly_saving = salary * 0.20
# Проверяем, может ли он купить смартфон с одной зарплаты
if monthly_saving >= smartphone_cost:
print("Денис может купить смартфон сразу, с одной зарплаты!")
else:
# Используем цикл while для симуляции процесса накопления
accumulated_sum = 0 # Переменная для хранения накопленной суммы
total_months = 0 # Счетчик месяцев
while accumulated_sum < smartphone_cost:
accumulated_sum += monthly_saving # Каждый месяц добавляем к накоплениям
total_months += 1 # Увеличиваем счетчик месяцев
# Рассчитываем полные годы и оставшиеся месяцы
years = total_months // 12
months = total_months % 12
# Готовим строки для вывода с правильными окончаниями
year_str = ""
month_str = ""
# Формируем строку для лет (используем условия для правильной грамматики)
if years > 0:
if years % 10 == 1 and years % 100 != 11:
year_str = f"{years} год"
elif 2 <= years % 10 <= 4 and (years % 100 < 10 or years % 100 >= 20):
year_str = f"{years} года"
else:
year_str = f"{years} лет"
# Формируем строку для месяцев (используем условия для правильной грамматики)
if months > 0:
if months == 1:
month_str = "1 месяц"
elif 2 <= months <= 4:
month_str = f"{months} месяца"
else:
month_str = f"{months} месяцев"
# Собираем и выводим итоговый результат
result_parts = []
if year_str:
result_parts.append(year_str)
if month_str:
result_parts.append(month_str)
print("Накопление займет: " + " и ".join(result_parts))1 - Read the task and understand what needs to be done
2 - The example shows how the input data will be provided and what output is expected
3 - Write the code considering the input, output, and the task itself.
1 - The “Run” button executes your code only on one set of input data, and you’ll see the result in the output window.
2 - The “Test on All Cases” button runs your code against all test cases. If all tests pass, a banner will appear. If even one test fails, it will be highlighted in red.
To change the input data, click the “Run Test” button next to the input data you want to execute.
1 - Input Data is the window containing the values loaded into your program in place of input()
2 - Program Output is the window showing what your program prints. If it’s green, the output matches the expected result; if red, there are differences.
3 - Expected Output is the reference value used to verify the solution.
1 - Green means the program produced the correct output
2 - Red means the program’s output didn’t match the expected output for this data. The program output and the expected output must be identical, including spaces and punctuation!
If you see this banner, congratulations — everything is correct.
1 - The first 10 tasks are quite easy and contain hints covering only the essential parts of the topic.
2 - The next 10 tasks are medium difficulty. Their hints differ from the easy ones and reveal new aspects of the topic.
3 - The hardest tasks have no hints. Often, they include additional topics, so sometimes it’s better to move on and return later. Read the hints carefully — they offer new ways to solve already familiar problems.
1 - Each block contains a “Theory” section.
2 - It always includes a detailed video.
3 - There is also a detailed guide with all the necessary theory and code examples.
1 - Click the “Report an Error / Social Media” button
2 - Here you can describe the error you encountered.
3 - You’ll also find our social media links here — follow us and help us improve.
🎉 Congratulations! 🎉
You did an excellent job with the task! It was a challenging problem, but you found the correct solution. You are one step closer to mastering programming! Keep up the good work, because every stage you pass makes you even stronger.
AD
Advertisement
Running your code...