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CSES Problem Set

Coin Grid


Task | Statistics


CSES - Coin GridCSES - Coin Grid

Time limit:1.00 s Memory limit:512 MB

There is an $n \times n$ grid whose each square is empty or has a coin. On each move, you can remove all coins in a row or column.

What is the minimum number of moves after which the grid is empty?

Input

The first input line has an integer $n$: the size of the grid. The rows and columns are numbered $1,2,\dots,n$.

After this, there are $n$ lines describing the grid. Each line has $n$ characters: each character is either . (empty) or o (coin).

Output

First print an integer $k$: the minimum number of moves. After this, print $k$ lines describing the moves.

On each line, first print $1$ (row) or $2$ (column), and then the number of a row or column. You can print any valid solution.

Constraints
Example

Input:
3
..o
o.o
...


Output:
2
1 2
2 3