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Problem B
Ardi, The Hungry Aardvark

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This is the ant farm specified in Sample 1

Ardi the aardvark arrived at the pet shop tired and hungry. Ardi spotted an ant farm on the next shelf, already populated with lots of yummy-looking crispy ants. Amazingly, it was so 2-dimensional that she could see every tunnel and avery ant. Immediately, Ardi begins plotting how to satisfy her hunger after the shop closes. Ardi knows the length of her tongue is 30 cm., which is typical for aardvarks. She can estimate the lengths of the tunnel sections and can count the number of ants in them. Her objective will be to get in and out as quickly as possible with a limited number of probes of her long tongue to reach the maximum number of ants. Ardi wants you to help with the calculations since aardvarks are not known for their computing prowess.

In preparation for her meal, Ardi wants you to consider multiple (not necessarily all) maximal-length paths that her tongue can take into the tunnels of the ant farm. By doing these calculations in advance, she hopes you can help her to choose the optimal paths to follow during her limited feeding time.

For each possible path, Ardi records the length of each segment and the turn at each junction with an L (for left) and R (for right), with left and right being relative to the direction her tongue would be going. (You may assume that left and right are the only options.) Ardi does not waste time recording data for segments that are clearly beyond the full 30-centimeter reach of her tongue. Any actual probe with her long tongue down a tunnel will be terminated at either a dead end or somewhere in the middle of a segment (at the full reach of her tongue). Note that the tunnels are too narrow for her to double back with her tongue to go down a different branch during the same probe. Very importantly, Ardi records the number of reachable ants in each segment for a given path, the intent being for you to calculate the maximum total number of ants her tongue can reach.

Input

The first line of the input contains two integers, the first indicating the number of different paths Ardi has had time to record through the ant farm tunnels, and the second indicating how many probes with her tongue that she will have the time to actually make once she gets her chance. Each subsequent line details one of the maximal-length paths Ardi wants you to examine, given in no particular order. Each possible path begins with its number of segments. Following that is the sequence of tunnel segments, each segment represented by 4 components: the letter ’R’ (for turn right) or ’L’ (for turn left), the estimated full length (a positive integer) of the segment (even if its far end is beyond her reach), the number of reachable ants in the segment (there could be more beyond her reach), and finally a lowercase letter designating the node (which could be a junction) at the far end of the segment. (Nodes are assigned in the order they are first examined, starting with ’a’.) Ardi will never ask about making more than 20 probes, no node or segment will be repeated in the same probe, no two branches will merge further down the possible paths, and there will never be more than 100 ants in any given tunnel segment.

The ant farm figure shows the configuration for the sample inputs, which are the same except for the number of probes Ardi has time to make. The red annotations indicate the path details. Potential path 2 can each reach $4+7+3+1=15$ ants. So with time for only one probe as in sample 1, $15$ is the maximum count. But with time for two probes as in sample 2, note that paths 2 and 6 are totally disjoint, and while paths 3 and 4 have more ants than path 2, many of them are already gobbled up in the probe of path 6. Therefore, the $27$ ants from paths 2 and 6 are optimal. Similar arguments can be made for sample 3.

Output

Print a single integer indicating the maximum number of ants Ardi can catch with the given number of probes through some combination of the provided maximal paths. This will at least get Ardi started.

Sample Input 1 Sample Output 1
6 1
2 L 10 4 b   R 4 1 c  
4 L 10 4 b   L 13 7 d   L 5 3 e  R 3 1 f  
4 L 10 4 b   L 13 7 d   L 5 3 e  L 10 0 g  
3 L 10 4 b   L 13 7 d   R 4 3 h  
2 R 15 4 i   R 10 3 j  
2 R 15 4 i   L 20 8 k  
15
Sample Input 2 Sample Output 2
6 2
2 L 10 4 b   R 4 1 c  
4 L 10 4 b   L 13 7 d   L 5 3 e  R 3 1 f  
4 L 10 4 b   L 13 7 d   L 5 3 e  L 10 0 g  
3 L 10 4 b   L 13 7 d   R 4 3 h  
2 R 15 4 i   R 10 3 j  
2 R 15 4 i   L 20 8 k  
27
Sample Input 3 Sample Output 3
6 3
2 L 10 4 b   R 4 1 c  
4 L 10 4 b   L 13 7 d   L 5 3 e  R 3 1 f  
4 L 10 4 b   L 13 7 d   L 5 3 e  L 10 0 g  
3 L 10 4 b   L 13 7 d   R 4 3 h  
2 R 15 4 i   R 10 3 j  
2 R 15 4 i   L 20 8 k  
30

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