row reduce %7B%7B1%2C-1%2C1%2C-1%2C0%7D%2C%7B1000%2C800%2C0%2C0%2C-5%7D%2C%7B0%2C-800%2C-600%2C0%2C-10%7D%2C%7B0%2C0%2C600%2C500%2C10%7D%7D

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