output_description: Print the maximum possible score of A.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N M Q
      a_1 b_1 c_1 d_1
      :
      a_Q b_Q c_Q d_Q
attempt: N, M, Q = map(int, (input().split()))
  A = []
  
  if N == 10:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
                          for a6 in range(a5, M + 1):
                              for a7 in range(a6, M + 1):
                                  for a8 in range(a7, M + 1):
                                      for a9 in range(a8, M + 1):
                                          for a10 in range(a9, M + 1):
                                              A.append(
                                                  [
                                                      a1,
                                                      a2,
                                                      a3,
                                                      a4,
                                                      a5,
                                                      a6,
                                                      a7,
                                                      a8,
                                                      a9,
                                                      a10,
                                                  ]
                                              )
  
  if N == 9:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
                          for a6 in range(a5, M + 1):
                              for a7 in range(a6, M + 1):
                                  for a8 in range(a7, M + 1):
                                      for a9 in range(a8, M + 1):
                                          A.append([a1, a2, a3, a4, a5, a6, a7, a8, a9])
  if N == 8:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
                          for a6 in range(a5, M + 1):
                              for a7 in range(a6, M + 1):
                                  for a8 in range(a7, M + 1):
                                      A.append([a1, a2, a3, a4, a5, a6, a7, a8])
  
  if N == 7:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
                          for a6 in range(a5, M + 1):
                              for a7 in range(a6, M + 1):
  
                                  A.append([a1, a2, a3, a4, a5, a6, a7])
  if N == 6:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
                          for a6 in range(a5, M + 1):
  
                              A.append([a1, a2, a3, a4, a5, a6])
  if N == 5:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
                      for a5 in range(a4, M + 1):
  
                          A.append([a1, a2, a3, a4, a5])
  if N == 4:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
                  for a4 in range(a3, M + 1):
  
                      A.append([a1, a2, a3, a4])
  if N == 3:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
              for a3 in range(a2, M + 1):
  
                  A.append([a1, a2, a3])
  if N == 2:
      for a1 in range(1, M + 1):
          for a2 in range(a1, M + 1):
  
              A.append([a1, a2])
  ans = 0
  
  abcd = []
  for i in range(Q):
      abc = list(map(int, (input().split())))
      abcd.append(abc)
  dd = []
  for i in range(len(A)):
      d = 0
      for j in range(Q):
          if A[i][abcd[j][1] - 1] - A[i][abcd[j][0] - 1] == abcd[j][2]:
              d += abcd[j][3]
      dd.append(d)
  print(str(max(dd)))
  
problem_description: Statement
  
  Given are positive integers N, M, Q, and Q quadruples of integers ( a_i , b_i
  , c_i , d_i ).
  
  Consider a sequence A satisfying the following conditions:
  
    * A is a sequence of N positive integers.
    * 1 \leq A_1 \leq A_2 \le \cdots \leq A_N \leq M.
  
  Let us define a score of this sequence as follows:
  
    * The score is the sum of d_i over all indices i such that A_{b_i} - A_{a_i} = c_i. (If there is no such i, the score is 0.)
  
  Find the maximum possible score of A.
samples: [{"input": "3 4 3\n    1 3 3 100\n    1 2 2 10\n    2 3 2 10", "output": "110\n    \n\nWhen A = \\\\{1, 3, 4\\\\}, its score is 110. Under these conditions, no sequence\nhas a score greater than 110, so the answer is 110.\n\n* * *"}, {"input": "4 6 10\n    2 4 1 86568\n    1 4 0 90629\n    2 3 0 90310\n    3 4 1 29211\n    3 4 3 78537\n    3 4 2 8580\n    1 2 1 96263\n    1 4 2 2156\n    1 2 0 94325\n    1 4 3 94328", "output": "357500\n    \n\n* * *"}, {"input": "10 10 1\n    1 10 9 1", "output": "1"}]