I solved it in less than 15 minutes while walking my dog, no pen or paper. But I wouldn't claim to be a random person without math skills. And my very first guess was correct.
It was a fun puzzle though and I'm surprised I didn't know it already. Thanks for sharing.
Why do you need to merge counts if you look for unique elements? Isn't the count always 1 for each element present? Isn't the key to shard your chunks so each element can appear in at most one chunk?
Why are those 5 people there? How can I be sure they'd be killed? How can I be sure they don't want to be killed. It's not wrong not to kill the one man because you can't be sure of the situation.
Some googling suggests that it's $200 per metric ton, is that right?
That would put the cost of capturing the world's entire footprint at $7T per year. That's a lot of money but seems pretty close to worth doing. Especially given that once we decide to do it, it will get cheaper quickly.
Some countries start on a Friday or Saturday and until 2022 Iran could start any day of the week although never at 3AM.