If there is no power to crank the engine then the alternator wouldn't come into effect because all that does is charge the battery once the engine is running. I would start with the battery and its' connections. If they are good and the battery load tests ok then move on to visual inspection of things like the fuses, relays (especially crank and starter relays), electrical connections at the fuse block, etc. If the car was dead after sitting for any length of time verify the headlamps or domelamps weren't left on and proceed from there.
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