Problem Statement  
Your hobby is collecting postmarks. There is a total of N distinct postmarks, numbered from 0 to N1. Their prices are given in the int[] prices, where the ith element (0indexed) is the price of postmark i. Your goal is to collect as many distinct postmarks as possible. The postmarks you currently have are given in the int[] have. Initially, you have no money. You can sell postmarks to get money to buy different postmarks. Return the maximum number of distinct postmarks you can collect.  
Definition  
 
Constraints  
  N will be between 1 and 50, inclusive.  
  prices will contain exactly N elements.  
  Each element of prices will be between 1 and 1,000,000, inclusive.  
  have will contain between 0 and N elements, inclusive.  
  All elements of have will be distinct.  
  Each element of have will be between 0 and N1, inclusive.  
Examples  
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