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x x              x x
x   xxxxx  xxxxx   x
x                  x
x x      xx      x x
x x x x  xx  x x x x
x x      xx      x x
x x x x  xx  x x x x
x x              x x
x x     o        x x
x x xxx      x   x x
x x  ux      x   x x
x x xxx      x   x x
x x   o    O     x x
x                x x
x   xxxxx  xxxxx   x
x x              x x
x                  x
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