.SP..
XS.S.
.SSX.
...S.
....X

Flowers are X, P is you. The grid is NxN. Number of flowers is K.
S are stones, fragrances need to travel around stones.
Find the most fragrant flower at your location (P).

Fragrance travels on a Manhattan distance, decays linearly:

F = F_0 - R d
F_0 is constant for all flowers,
R is a constant decay rate,
d is Manhattan distance.

char grid[][];
Pair<int, int> person;
List<Pair<int, int>> flowers;
List<Pair<int, int>> stones;

private int[] dx = {0,-1,0,1};
private int[] dy = {1,0,-1,0};
public int[] findMostFragnant(char[][] grid, int[] person, List<int[]>    flowers, List<int[]> stones){
    if(flower == null || flowers.size() == 0){
	  return null;
    }
    Queue<int[][]> q = new LinkedList<>();
    q.add(new int[]{person[0], person[1]});
    boolean[][] visited = new boolean[grid.length][grid[0].length];
    visited[person[0]][person[1]] = true;
    while(!q.isEmpty()){
        int size = q.size();
        for(int i = 0; i < size; i++){
	  	int[] pos = q.poll();
		int x = pos[0];
		int y = pos[1];
		for(int j = 0; j < 4; j++){
int nx = x + dx[j];
int ny = y + dy[j];
if(nx < 0 || ny < 0 || nx >= grid.size || ny >= grid[0].size || grid[nx][ny] = ‘S’ || visited[nx][ny]){
		continue;
}
if(grid[nx][ny] == ‘X’){
    return new int[]{nx, ny};
}
visited[nx][ny] = true;
q.add(new int[]{nx, ny});


}
  }
    }
    return null;
}