This [video(copied with time stamp)](https://youtu.be/klRSzyMKHwU?t=662) presents an approach to solving problem [1665C](https://codeforces.net/problemset/problem/1665/C) and I understood the broad approach but I am not able to understand that if we have the sum of left over vertices after considering infection is greater than the number of injection operations remaining we directly say that x is not possible, but shouldn't we also consider the fact that even if we have less injections left, they would all still spread in parallel at any given time?↵
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For example lets say that x = 3 and the sum of count values is 4. And this value comes from two sets comprising of two sibling nodes. Then it is possible to infect all of them in 3 seconds, because once we infect one of them the infection spreads to the sibling. So this is why I have this doubt, maybe I might have misunderstood something in which case I would really appreciate any help
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For example lets say that x = 3 and the sum of count values is 4. And this value comes from two sets comprising of two sibling nodes. Then it is possible to infect all of them in 3 seconds, because once we infect one of them the infection spreads to the sibling. So this is why I have this doubt, maybe I might have misunderstood something in which case I would really appreciate any help