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Hey there and welcome back.

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Let's get started with another interesting coding interview question, which is the task scheduler question.

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The question reads you are given an array of CPU tasks, each represented by letters A to Z, and a

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cooling time in each cycle or interval allows the completion of one task.

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Tasks can be completed in any order, but there is a constraint.

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Identical tasks must be separated by at least n intervals.

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Due to cooling time returned the minimum number of intervals required to complete all tasks.

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So this is the question at hand, and we are given a few examples so that we can thoroughly understand

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the question.

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So the first example over here is the input c e c e c okay.

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And n is given as two.

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Now when n is equal to two, it would mean that if you are doing, for example a task C, then when

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you have to wait two units of time to do another task C okay, so that's what's given over here.

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Identical tasks must be separated by at least n intervals due to cooling time.

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So in this case n is equal to two.

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And that's why two identical tasks which is in this case c and c have to be separated by two intervals

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okay.

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So that's the constraint in the question.

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And we are asked to identify the minimum number of intervals required to complete all tasks.

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So in this example we have a total of six tasks.

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And n is equal to two.

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And the expected output is equal to eight which is c.

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Then we do task e.

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Then we have to stay idle for one interval.

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And then again we can do c e.

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And again we stay idle for an interval and we again do c and e okay.

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So that's c e idle c e idle and c e.

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So this over here is a total of eight intervals because you have 12345678 okay.

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So this is the question.

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Now we're given one more example.

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So if the input is c e c e c and n is equal to three, the output expected is equal to ten.

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And because n is equal to three over here between two c tasks you have to leave three intervals for

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cooling okay.

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And the output is ten because c e idle idle c e idle idle c e would be the best way or the way with

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the least number of intervals for completing the input tasks.

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Okay, so the expected output in this case is ten.

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So this is the question at hand.

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Now in the next video let's discuss the approach that we can take to solve this question.