Question

Выходя на пробежку Рита берёт с собой телефон для прослушивания музыки и беспроводные наушники. Перед каждой пробежкой Рита заряжает наушники, и этой зарядки хватает на A минут прослушивания музыки. Рита решила, что каждый день она будет тренироваться на минуту дольше, чем в предыдущий день. То есть если в первый день Рита бегала и слушала музыку в течение B минут, во второй день она будет бегать B + 1 минуту, в третий день — B + 2 минуты и т.д. Если заряда наушников хватает на большее время, чем продолжительность пробежки, то неиспользованный заряд накапливается и может быть использован в последующие дни. Емкость аккумулятора наушников можно считать неограниченной. Определите, в какой день Рите впервые не хватит заряда для прослушивания музыки во время всей пробежки.

Answer 1

Ответ:

a = int(input())

b = int(input())

left = 0

right = 2 * 10 ** 9 + 1

while right - left > 1:

   mid = (left + right) // 2

   plus = a * mid

   minus = (b + b + mid - 1) * mid // 2

   if plus >= minus:

       left = mid

   else:

       right = mid

print(right)

Объяснение:

Перебором ищем нужное число.

Answer 2

Problem Analysis

Rita goes for a run and takes her phone and wireless headphones with her. Before each run, she charges the headphones, and the charge lasts for A minutes of music playback. Rita decides to increase her running time by 1 minute each day. If the headphones have more charge than the duration of the run, the unused charge accumulates and can be used on subsequent days. We need to determine on which day Rita will first run out of charge for listening to music during the entire run.

Solution

To solve this problem, we can use a simple loop to iterate through each day and keep track of the total charge required for the run. We will compare this total charge with the initial charge of the headphones. Once the total charge exceeds the initial charge, we will know that Rita does not have enough charge to listen to music for the entire run.

Let's assume the initial charge of the headphones is A minutes, and Rita increases her running time by 1 minute each day. We can use a variable `total_charge` to keep track of the total charge required for the run. We will initialize `total_charge` to A and increment it by 1 each day. We will also use a variable `day` to keep track of the current day.

Here is the step-by-step algorithm to solve the problem:

1. Initialize `total_charge` to A. 2. Initialize `day` to 1. 3. Repeat the following steps until `total_charge` exceeds the initial charge of the headphones: - Increment `total_charge` by 1. - Increment `day` by 1. 4. The value of `day` will be the day on which Rita first runs out of charge for listening to music during the entire run.

Let's implement this algorithm in code:

A = # initial charge of the headphones
total_charge = A
day = 1

while total_charge <= A:
    total_charge += 1
    day += 1

# The value of `day` will be the day on which Rita first runs out of charge for listening to music during the entire run.

Please provide the value of A, and I will calculate the day for you.