code in the language of your choice:

A site has 4,320,000 users. The users are sequentially numbered -- each user has a user_id between 1 and 4320000.

You want to slowly roll out a new feature to all users, at a consistent rate of X users per second. The roll-out should start at noon today, beginning with the newest user (id 4320000). The rollout should last two days, so user_id 1 gets the feature around noon two days from now.

$Write a function to determine whether the feature is currently enabled for a given user_id:

can_use_new_feature(int user_id) - bool.

Question

code in the language of your choice:

A site has 4,320,000 users. The users are sequentially numbered -- each user has a user_id between 1 and 4320000.

You want to slowly roll out a new feature to all users, at a consistent rate of X users per second.  The roll-out should start at noon today, beginning with the newest user (id 4320000).  The rollout should last two days, so user_id 1 gets the feature around noon two days from now.  

$Write a function to determine whether the feature is currently enabled for a given user_id:

can_use_new_feature(int user_id) -> bool.

Anonymous · Accepted Answer

Total seconds in 2 days = 172800 
Divide total users 4320000/172800(seconds) = 25 users processed every second

global start_time = unix_timestamp(start date noon)
global users_per_second = 25
global total_users = 4320000

function can_use_new_feature(user_id) {
    var current_timestamp = unix_timestamp(current_time)
    var elapsed_seconds = timestamp_diff_to_seconds(current_timestamp, start_time)
    var processed_users = total_users - (users_per_second * elapsed_seconds)

return (bool) user_id >=processed_users
}

Anonymous · Answer

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