Data=. }: freads'/tmp/input.txt'
houses=: 3 : '+/\ (0 0), (4 2$0 1 1 0 0 _1 _1 0){~ ''^>v<'' i. y'
# part 1
{. $ ~. houses Data
# part 2
santa=. 2 | i. # Data
robo=. -. santa
{. $ ~. (santa&# ,&shouses robo&#) Data
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