const string base32 = "0123456789bcdefghjkmnpqrstuvwxyz"; // (geohash-specific) Base32 map
/**
* Returns all 8 adjacent cells to specified geohash.
*
* @param {string} geohash - Geohash neighbours are required of.
* @returns {{n,ne,e,se,s,sw,w,nw: string}}
* @throws Invalid geohash.
*/
public static GeocodeMatrix Neighbours(string code)
{
return(GeocodeMatrix.Create(code)
.Add(adjacent(code, Direction.N))
.Add(adjacent(adjacent(code, Direction.N), Direction.E))
.Add(adjacent(code, Direction.E))
.Add(adjacent(adjacent(code, Direction.S), Direction.E))
.Add(adjacent(code, Direction.S))
.Add(adjacent(adjacent(code, Direction.S), Direction.W))
.Add(adjacent(code, Direction.W))
.Add(adjacent(adjacent(code, Direction.N), Direction.W)));
}
public bool Exists(GeocodeMatrix matrix) => matrices.Exists(matrix);
public void Add(GeocodeMatrix matrix) => matrices.Add(matrix);
public IEnumerable <string> f(GeocodeMatrix m) => m.Neighbours().Select(x => x.Code);