We wish to find the sum of $40$ given numbers using $40$ processors. Initially, each processor displays the number $0$ on its screen. Each processor can add the number on its screen with a number entered directly (only the given numbers can be entered directly into the processors) or transferred from another processor in a unit time. Whenever a number is transferred from one processor to another, the former processor resets to zero. Determine the minimum time required to compute the desired sum.

Let's think step by step and output the final answer within \boxed{}.
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