output_description: Print \displaystyle \sum_{L=1}^{N-1} \sum_{R=L+1}^{N} X_{L,R}.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      P_1 P_2 \ldots P_N
attempt: n = int(input())
  p = list(map(int, input().split()))
  x = 0
  for l in range(n - 1):
      for i in range(2, n - l):
          if p[l] <= p[l + 1]:
              first = p[l + 1]
              second = p[l]
          else:
              first = p[l]
              second = p[l + 1]
          if i != 2:
              for k in range(1, i - 1):
                  if p[l + k + 1] >= first:
                      second = first
                      first = p[l + k + 1]
                  elif p[l + k + 1] > second:
                      second = p[l + k + 1]
              x += second
          else:
              x += second
  print(int(x))
  
problem_description: Statement
  
  Given is a permutation P of \\{1, 2, \ldots, N\\}.
  
  For a pair (L, R) (1 \le L \lt R \le N), let X_{L, R} be the second largest
  value among P_L, P_{L+1}, \ldots, P_R.
  
  Find \displaystyle \sum_{L=1}^{N-1} \sum_{R=L+1}^{N} X_{L,R}.
samples: [{"input": "3\n    2 3 1", "output": "5\n    \n\nX_{1, 2} = 2, X_{1, 3} = 2, and X_{2, 3} = 1, so the sum is 2 + 2 + 1 = 5.\n\n* * *"}, {"input": "5\n    1 2 3 4 5", "output": "30\n    \n\n* * *"}, {"input": "8\n    8 2 7 3 4 5 6 1", "output": "136"}]