pub fn living_neighbors(&self, index: Index) -> usize {
        index
            .neighbors()
            .iter()
            .filter(|index| self.is_living(*index))
            .count()
    }
/// The number of live neighbors of the cell at the given index within the grid.
The number of live neighbors of the cell at the given index within the grid.
The number of live neighbors of the cell at the given index within the grid .
pub fn living_neighbors(&self, index: Index) -> usize {
        index
            .neighbors()
            .iter()
            .filter(|index| self.is_living(*index))
            .count()
    }
pub fn living_neighbors ( & self , index : Index ) -> usize { index . neighbors ( ) . iter ( ) . filter ( | index | self . is_living ( * index ) ) . count ( ) }
The number of live neighbors of the cell at the given index within the grid.
The number of live neighbors of the cell at the given index within the grid .
&self
index
Index
&self
index
Index