Curious George plays around on a planar grid. George can move one space at a time: left, right, up or down.
That is, from (x,y) George can go to (x+1,y), (x−1,y),(x,y+1), or (x,y−1).
George can access any point (x,y) where the sum of the digits of ∣x∣ + the sum of the digits of ∣y∣ is ≤19.
How many points can George access if he starts at (0,0) including (0,0) itself?
Explicit Examples
- (59,79) is inaccessible because 5+9+7+9=30, and 30>19
- (−5,−7) is accessible because ∣−5∣+∣−7∣=12≤19
- (190,90) is not reachable, considering its neighbors are all not reachable.