- Time limit: 1.00 s
- Memory limit: 512 MB
There is an n \times n grid, and your task is to choose from each row and column some number of squares. How can you do that?
Input
The first input line has an integer n: the size of the grid. The rows and columns are numbered 1,2,\dots,n.
The next line has n integers a_1,a_2,\ldots,a_n: You must choose exactly a_i squares from the ith row.
The las line has n integers b_1,b_2,\ldots,b_n: You must choose exactly b_j squares from the jth column.
Output
Print n lines describing which squares you choose (X
means that you choose a square, .
means that you don't choose it). You can print any valid solution.
If it is not possible to satisfy the conditions print only -1.
Constraints
- 1 \le n \le 50
- 0 \le a_i \le n
- 0 \le b_j \le n
Example
Input:
5 0 1 3 2 0 1 2 2 0 1
Output:
..... ..X.. .XX.X XX... .....