I was playing survival on a different computer and the game crashed.

I was playing survival on a different computer and the game crashed. i restarted minecraft and the game didnt display in the "saved games" window. I closed minecraft. made a save of the game to a flash drive and took it with me. Im currently trying to recover the game on my usual computer. each time i try to do something it crashes. this current report is the result of me trying to start up a new world. started it up, downloaded map screen, then crash.

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