leetcode First Missing Positive hashset简单应用

 public class Solution {
     public int firstMissingPositive(int[] A) {
         HashSet<Integer> hash=new HashSet<Integer>();
         int count=0;
         int sum=0;

         for(int i:A)
         {
             if(i>0)
             {
                 hash.add(i);
             }
         }

          int beg=1;
          while(hash.contains(beg))
          {
              beg++;

          }

          return beg;

     }
 }

V

 public class Solution {
     public int firstMissingPositive(int[] A) {
         HashSet<Integer> hash=new HashSet<Integer>();
         int count=0;
         int sum=0;

         for(int i:A)
         {
             if(i>0)
             {
                 hash.add(i);
             }
         }

          int beg=1;
          while(hash.contains(beg))
          {
              beg++;

          }

          return beg;

     }
 }

w Code