output_description: Print the maximum possible happiness Takahashi can achieve.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N T
      A_1 B_1
      :
      A_N B_N
attempt: e = enumerate
  (n, t), *g = [list(map(int, t.split())) for t in open(0)]
  d = [0]
  g.sort()
  dp = []
  d = [0] * t
  for a, b in g:
      p = d[:]
      for i in range(a, t):
          v = d[i - a] + b
          if v > p[i]:
              p[i] = v
      dp += (p,)
      d = p
  a = m = 0
  for (*_, v), (_, w) in zip(dp[-2::-1], g[::-1]):
      if w > m:
          m = w
      if v + m > a:
          a = v + m
  print(a)
  
problem_description: Statement
  
  Takahashi is at an all-you-can-eat restaurant.
  
  The restaurant offers N kinds of dishes. It takes A_i minutes to eat the i-th
  dish, whose deliciousness is B_i.
  
  The restaurant has the following rules:
  
    * You can only order one dish at a time. The dish ordered will be immediately served and ready to eat.
    * You cannot order the same kind of dish more than once.
    * Until you finish eating the dish already served, you cannot order a new dish.
    * After T-0.5 minutes from the first order, you can no longer place a new order, but you can continue eating the dish already served.
  
  Let Takahashi's happiness be the sum of the deliciousness of the dishes he
  eats in this restaurant.
  
  What is the maximum possible happiness achieved by making optimal choices?
samples: [{"input": "2 60\n    10 10\n    100 100", "output": "110\n    \n\nBy ordering the first and second dishes in this order, Takahashi's happiness\nwill be 110.\n\nNote that, if we manage to order a dish in time, we can spend any amount of\ntime to eat it.\n\n* * *"}, {"input": "3 60\n    10 10\n    10 20\n    10 30", "output": "60\n    \n\nTakahashi can eat all the dishes within 60 minutes.\n\n* * *"}, {"input": "3 60\n    30 10\n    30 20\n    30 30", "output": "50\n    \n\nBy ordering the second and third dishes in this order, Takahashi's happiness\nwill be 50.\n\nWe cannot order three dishes, in whatever order we place them.\n\n* * *"}, {"input": "10 100\n    15 23\n    20 18\n    13 17\n    24 12\n    18 29\n    19 27\n    23 21\n    18 20\n    27 15\n    22 25", "output": "145"}]