leetcode First Missing Positive hashset简单应用

 1 public class Solution {

 2     public int firstMissingPositive(int[] A) {

 3         HashSet<Integer> hash=new HashSet<Integer>();

 4         int count=0;

 5         int sum=0;

 6         

 7         for(int i:A)

 8         {

 9             if(i>0)

10             {

11                 hash.add(i);

12             }

13         }

14          

15          int beg=1;

16          while(hash.contains(beg))

17          {

18              beg++;

19              

20              

21          }

22          

23          return beg;

24         

25        

26         

27     }

28 }

V

 1 public class Solution {

 2     public int firstMissingPositive(int[] A) {

 3         HashSet<Integer> hash=new HashSet<Integer>();

 4         int count=0;

 5         int sum=0;

 6         

 7         for(int i:A)

 8         {

 9             if(i>0)

10             {

11                 hash.add(i);

12             }

13         }

14          

15          int beg=1;

16          while(hash.contains(beg))

17          {

18              beg++;

19              

20              

21          }

22          

23          return beg;

24         

25        

26         

27     }

28 }

 

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