#D5431. Extension
Extension
Extension
We have a grid with A horizontal rows and B vertical columns, with the squares painted white. On this grid, we will repeatedly apply the following operation:
- Assume that the grid currently has a horizontal rows and b vertical columns. Choose "vertical" or "horizontal".
- If we choose "vertical", insert one row at the top of the grid, resulting in an (a+1) \times b grid.
- If we choose "horizontal", insert one column at the right end of the grid, resulting in an a \times (b+1) grid.
- Then, paint one of the added squares black, and the other squares white.
Assume the grid eventually has C horizontal rows and D vertical columns. Find the number of ways in which the squares can be painted in the end, modulo 998244353.
Constraints
- 1 \leq A \leq C \leq 3000
- 1 \leq B \leq D \leq 3000
- A, B, C, and D are integers.
Input
Input is given from Standard Input in the following format:
A B C D
Output
Print the number of ways in which the squares can be painted in the end, modulo 998244353.
Examples
Input
1 1 2 2
Output
3
Input
2 1 3 4
Output
65
Input
31 41 59 265
Output
387222020
inputFormat
Input
Input is given from Standard Input in the following format:
A B C D
outputFormat
Output
Print the number of ways in which the squares can be painted in the end, modulo 998244353.
Examples
Input
1 1 2 2
Output
3
Input
2 1 3 4
Output
65
Input
31 41 59 265
Output
387222020
样例
2 1 3 4
65