output_description: Print one longest string that is a subsequence of both s and t. If there are
  multiple such strings, any of them will be accepted.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      s
      t
attempt: a = list(map(input()))
  b = list(map(input()))
  
  k = max(len(a),len(b))
  
  dp = [['']*(len(b)+1) for i in range(len(a))]
  
  for i in range(len(a)):
  	for j in range(len(b)):
  		if a[i] == b[j]:
  			dp[i+1][j+1] = dp[i][j] + 1
  		else:
  			dp[i+1][j+1] = max(dp[i+1][j],dp[i][j+1])
  
  global ans = ""
  
  def rec(m,n):
  	if m == 0 and n == 0:
  		return ans
  	if a[m-1] == b[n-1]:
  		ans += a[m]
  		rec(m-1.n-1)
  	elif dp[m-1][n] > dp[m][n-1]:
  		rec(m-1,n)
  	else:
  		rec(m,n-1) 
  
  rec(len(a),len(b))
  print(ans)
problem_description: Statement
  
  You are given strings s and t. Find one longest string that is a subsequence
  of both s and t.
samples: [{"input": "axyb\n    abyxb", "output": "axb\n    \n\nThe answer is `axb` or `ayb`; either will be accepted.\n\n* * *"}, {"input": "aa\n    xayaz", "output": "aa\n    \n\n* * *"}, {"input": "a\n    z", "output": "The answer is `` (an empty string).\n\n* * *"}, {"input": "abracadabra\n    avadakedavra", "output": "aaadara"}]