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 }

 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 }

w Code

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时间： 2024-10-23 04:30:18

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