y: 20
x: 40
dx: 4, dy: 4 
i: 1 
fy: 3, y2: 2, sgn(dy): 1 
fx: 20, x2: 19, sgn(dx): 1 
i: 2 
fy: 4, y2: 2, sgn(dy): 1 
fx: 21, x2: 19, sgn(dx): 1 
i: 3 
fy: 5, y2: 2, sgn(dy): 1 
fx: 22, x2: 19, sgn(dx): 1 
dx: 4, dy: -4 
i: 1 
fy: 5, y2: 6, sgn(dy): -1 
fx: 16, x2: 15, sgn(dx): 1 
i: 2 
fy: 4, y2: 6, sgn(dy): -1 
fx: 17, x2: 15, sgn(dx): 1 
i: 3 
fy: 3, y2: 6, sgn(dy): -1 
fx: 18, x2: 15, sgn(dx): 1 
dx: 7, dy: 0 
i: 1 
fy: 6, y2: 6, sgn(dy): 0 
fx: 9, x2: 8, sgn(dx): 1 
i: 2 
fy: 6, y2: 6, sgn(dy): 0 
fx: 10, x2: 8, sgn(dx): 1 
i: 3 
fy: 6, y2: 6, sgn(dy): 0 
fx: 11, x2: 8, sgn(dx): 1 
i: 4 
fy: 6, y2: 6, sgn(dy): 0 
fx: 12, x2: 8, sgn(dx): 1 
i: 5 
fy: 6, y2: 6, sgn(dy): 0 
fx: 13, x2: 8, sgn(dx): 1 
i: 6 
fy: 6, y2: 6, sgn(dy): 0 
fx: 14, x2: 8, sgn(dx): 1 
dx: -4, dy: -4 
i: 1 
fy: 9, y2: 10, sgn(dy): -1 
fx: 11, x2: 12, sgn(dx): -1 
i: 2 
fy: 8, y2: 10, sgn(dy): -1 
fx: 10, x2: 12, sgn(dx): -1 
i: 3 
fy: 7, y2: 10, sgn(dy): -1 
fx: 9, x2: 12, sgn(dx): -1 
dx: 4, dy: -4 
i: 1 
fy: 13, y2: 14, sgn(dy): -1 
fx: 9, x2: 8, sgn(dx): 1 
i: 2 
fy: 12, y2: 14, sgn(dy): -1 
fx: 10, x2: 8, sgn(dx): 1 
i: 3 
fy: 11, y2: 14, sgn(dy): -1 
fx: 11, x2: 8, sgn(dx): 1 
dx: -7, dy: 0 
i: 1 
fy: 14, y2: 14, sgn(dy): 0 
fx: 14, x2: 15, sgn(dx): -1 
i: 2 
fy: 14, y2: 14, sgn(dy): 0 
fx: 13, x2: 15, sgn(dx): -1 
i: 3 
fy: 14, y2: 14, sgn(dy): 0 
fx: 12, x2: 15, sgn(dx): -1 
i: 4 
fy: 14, y2: 14, sgn(dy): 0 
fx: 11, x2: 15, sgn(dx): -1 
i: 5 
fy: 14, y2: 14, sgn(dy): 0 
fx: 10, x2: 15, sgn(dx): -1 
i: 6 
fy: 14, y2: 14, sgn(dy): 0 
fx: 9, x2: 15, sgn(dx): -1 
dx: -4, dy: -4 
i: 1 
fy: 17, y2: 18, sgn(dy): -1 
fx: 18, x2: 19, sgn(dx): -1 
i: 2 
fy: 16, y2: 18, sgn(dy): -1 
fx: 17, x2: 19, sgn(dx): -1 
i: 3 
fy: 15, y2: 18, sgn(dy): -1 
fx: 16, x2: 19, sgn(dx): -1 
dx: -4, dy: 4 
i: 1 
fy: 15, y2: 14, sgn(dy): 1 
fx: 22, x2: 23, sgn(dx): -1 
i: 2 
fy: 16, y2: 14, sgn(dy): 1 
fx: 21, x2: 23, sgn(dx): -1 
i: 3 
fy: 17, y2: 14, sgn(dy): 1 
fx: 20, x2: 23, sgn(dx): -1 
dx: -7, dy: 0 
i: 1 
fy: 14, y2: 14, sgn(dy): 0 
fx: 29, x2: 30, sgn(dx): -1 
i: 2 
fy: 14, y2: 14, sgn(dy): 0 
fx: 28, x2: 30, sgn(dx): -1 
i: 3 
fy: 14, y2: 14, sgn(dy): 0 
fx: 27, x2: 30, sgn(dx): -1 
i: 4 
fy: 14, y2: 14, sgn(dy): 0 
fx: 26, x2: 30, sgn(dx): -1 
i: 5 
fy: 14, y2: 14, sgn(dy): 0 
fx: 25, x2: 30, sgn(dx): -1 
i: 6 
fy: 14, y2: 14, sgn(dy): 0 
fx: 24, x2: 30, sgn(dx): -1 
dx: 4, dy: 4 
i: 1 
fy: 11, y2: 10, sgn(dy): 1 
fx: 27, x2: 26, sgn(dx): 1 
i: 2 
fy: 12, y2: 10, sgn(dy): 1 
fx: 28, x2: 26, sgn(dx): 1 
i: 3 
fy: 13, y2: 10, sgn(dy): 1 
fx: 29, x2: 26, sgn(dx): 1 
dx: -4, dy: 4 
i: 1 
fy: 7, y2: 6, sgn(dy): 1 
fx: 29, x2: 30, sgn(dx): -1 
i: 2 
fy: 8, y2: 6, sgn(dy): 1 
fx: 28, x2: 30, sgn(dx): -1 
i: 3 
fy: 9, y2: 6, sgn(dy): 1 
fx: 27, x2: 30, sgn(dx): -1 
dx: 7, dy: 0 
i: 1 
fy: 6, y2: 6, sgn(dy): 0 
fx: 24, x2: 23, sgn(dx): 1 
i: 2 
fy: 6, y2: 6, sgn(dy): 0 
fx: 25, x2: 23, sgn(dx): 1 
i: 3 
fy: 6, y2: 6, sgn(dy): 0 
fx: 26, x2: 23, sgn(dx): 1 
i: 4 
fy: 6, y2: 6, sgn(dy): 0 
fx: 27, x2: 23, sgn(dx): 1 
i: 5 
fy: 6, y2: 6, sgn(dy): 0 
fx: 28, x2: 23, sgn(dx): 1 
i: 6 
fy: 6, y2: 6, sgn(dy): 0 
fx: 29, x2: 23, sgn(dx): 1 
20 40
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