output_description: Print the amount you have left after shopping.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      X
      A
      B
attempt: n, m = map(int, input().split())
  l = []
  for i in range(m):
      l.append(list(map(int, input().split())))
  l.sort()
  xi = 0
  i = 0
  x = [None for i in range(10**5)]
  while i < m:
      x[l[0][0]] = 0
      if l[i][0] == xi:
          if x[l[i][1]] == None:
              x[l[i][1]] = l[i][2] + x[l[i][0]]
              i += 1
          else:
              print("No")
              break
      else:
          xi += 1
  if i < m:
      pass
  else:
      print("Yes")
  
problem_description: Statement
  
  You went shopping to buy cakes and donuts with X yen (the currency of Japan).
  
  First, you bought one cake for A yen at a cake shop. Then, you bought as many
  donuts as possible for B yen each, at a donut shop.
  
  How much do you have left after shopping?
samples: [{"input": "1234\n    150\n    100", "output": "84\n    \n\nYou have 1234 - 150 = 1084 yen left after buying a cake. With this amount, you\ncan buy 10 donuts, after which you have 84 yen left.\n\n* * *"}, {"input": "1000\n    108\n    108", "output": "28\n    \n\n* * *"}, {"input": "579\n    123\n    456", "output": "0\n    \n\n* * *"}, {"input": "7477\n    549\n    593", "output": "405"}]