output_description: Print the maximum possible total joyfulness of the two contests.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      L_1 R_1
      L_2 R_2
      \vdots
      L_N R_N
attempt: s = input()
  l = [0 for i in range(len(s) + 1)]
  if s[0] == "<":
      cnt = 1
      for i in range(0, len(s)):
          if s[i] == "<":
              l[i + 1] = max(cnt, l[i + 1])
              cnt += 1
          else:
              break
  if s[-1] == ">":
      cnt = 1
      for i in range(len(s) - 1, -1, -1):
          if s[i] == ">":
              l[i] = max(cnt, l[i])
              cnt += 1
          else:
              break
  for i in range(1, len(s)):
      if s[i - 1 : i + 1] == "><":
          # 左側検索
          cnt = 1
          for j in range(i - 1, -1, -1):
              if s[j] == ">":
                  l[j] = max(cnt, l[j])
                  cnt += 1
              else:
                  break
          # 右側検索
          cnt = 1
          for j in range(i, len(s)):
              if s[j] == "<":
                  l[j + 1] = max(cnt, l[j])
                  cnt += 1
              else:
                  break
  ans = sum(l)
  print(ans)
  
problem_description: Statement
  
  10^9 contestants, numbered 1 to 10^9, will compete in a competition. There
  will be two contests in this competition.
  
  The organizer prepared N problems, numbered 1 to N, to use in these contests.
  When Problem i is presented in a contest, it will be solved by all contestants
  from Contestant L_i to Contestant R_i (inclusive), and will not be solved by
  any other contestants.
  
  The organizer will use these N problems in the two contests. Each problem must
  be used in exactly one of the contests, and each contest must have at least
  one problem.
  
  The _joyfulness_ of each contest is the number of contestants who will solve
  all the problems in the contest. Find the maximum possible total joyfulness of
  the two contests.
samples: [{"input": "4\n    4 7\n    1 4\n    5 8\n    2 5", "output": "6\n    \n\nThe optimal choice is:\n\n  * Use Problem 1 and 3 in the first contest. Contestant 5, 6, and 7 will solve both of them, so the joyfulness of this contest is 3.\n  * Use Problem 2 and 4 in the second contest. Contestant 2, 3, and 4 will solve both of them, so the joyfulness of this contest is 3.\n  * The total joyfulness of these two contests is 6. We cannot make the total joyfulness greater than 6.\n\n* * *"}, {"input": "4\n    1 20\n    2 19\n    3 18\n    4 17", "output": "34\n    \n\n* * *"}, {"input": "10\n    457835016 996058008\n    456475528 529149798\n    455108441 512701454\n    455817105 523506955\n    457368248 814532746\n    455073228 459494089\n    456651538 774276744\n    457667152 974637457\n    457293701 800549465\n    456580262 636471526", "output": "540049931"}]