3951.Infinite Maze

Time Limit: 1s Memory Limit: 256MB

We've got a rectangular n \times m-cell maze. Each cell is either passable, or is a wall (impassable). A little boy found the maze and cyclically tiled a plane with it so that the plane became an infinite maze. Now on this plane cell (x,y) is a wall if and only if cell 3951_1.png is a wall.In this problem 3951_2.png is a remainder of dividing number a by number b.The little boy stood at some cell on the plane and he wondered whether he can walk infinitely far away from his starting position. From cell (x,y) he can go to one of the following cells: (x,y-1), (x,y+1), (x-1,y) and (x+1,y), provided that the cell he goes to is not a wall.

Input Format(From the terminal/stdin)

Input The first line contains two space-separated integers n and m (1 \le n,m \le 1500) - the height and the width of the maze that the boy used to cyclically tile the plane.Each of the next n lines contains m characters - the description of the labyrinth. Each character is either a "#", that marks a wall, a ".", that marks a passable cell, or an "S", that marks the little boy's starting point. The starting point is a passable cell. It is guaranteed that character "S" occurs exactly once in the input.

Output Format(To the terminal/stdout)

Output Print "Yes" (without the quotes), if the little boy can walk infinitely far from the starting point. Otherwise, print "No" (without the quotes).

Sample Input 1

Copy
5 4
##.#
##S#
#..#
#.##
#..#
 · \n
    \n
    \n
    \n
    \n
    \n

Sample Output 1

Copy
Yes
   \n

Sample Input 2

Copy
5 4
##.#
##S#
#..#
..#.
#.##
 · \n
    \n
    \n
    \n
    \n
    \n

Sample Output 2

Copy
No
  \n

Hints

In the first sample the little boy can go up for infinitely long as there is a "clear path" that goes vertically. He just needs to repeat the following steps infinitely: up, up, left, up, up, right, up.In the second sample the vertical path is blocked. The path to the left doesn't work, too - the next "copy" of the maze traps the boy.

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