ICPC Central K
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Participants are given a maze which is a map of size \(h \times w\), which contain cells denoted by one of the following symbols:
#: Obstacle cell.+: From this cell, the car can move to the adjacent square (Left, Right, Up, Down).L: From this cell, the car can only move left.R: From this cell, the car can only move right.U: From this cell, the car can only move up.D: From this cell, the car can only move down.
Each time unit, the car moves \(1\) cell according to the symbol of the map. Mr. Tuan wants to know how many valid ways to move in all the time \(t\) allows (starting from any position). Note that, car hitting an obstacle or leaving the map are considered illegal and do not count as a valid way.
Input
- The first line contains \(3\) natural numbers \(h, w\) and \(t\).
- Next \(h\) lines contains the symbols of maze.
Constraints
- \(1 \le h \cdot w \le 100\)
- \(1 \le t \le 10^9\)
Output
- Print the number of valid way. Since result may be too big, print it after taking modulo \(10^9 + 7\).
Example
Test 1
Input
2 2 10
RD
UL
Output
4
Note
Explanation Example 1: From any coordinate, there is one valid move. So there are \(4\) ways in total.
Test 2
Input
3 3 2
RD#
U+#
#LR
Output
7
Note
Explanation Example 2: From coordinates \((1,1)\) there is one valid way to move, RD. From coordinates \((1,2)\) there are \(3\) valid ways to move: DU, DL, DR. From coordinates \((2,1)\) there is \(1\) way UR. From coordinates \((2,2)\) there are \(2\) ways: UD, LU. The other coordinates with no valid way of moving. So there are \(7\) ways in total.
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