FilesExpand file tree

 master

/

DeleteAndEarn740.java

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

78 lines (72 loc) · 2.13 KB

 master

/

DeleteAndEarn740.java

Copy path

Top

File metadata and controls

• Code
• Blame

78 lines (72 loc) · 2.13 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

/**

* Given an array nums of integers, you can perform operations on the array.

*

* In each operation, you pick any nums[i] and delete it to earn nums[i]

* points. After, you must delete every element equal to nums[i] - 1 or

* nums[i] + 1.

*

* You start with 0 points. Return the maximum number of points you can earn

* by applying such operations.

*

* Example 1:

* Input: nums = [3, 4, 2]

* Output: 6

* Explanation:

* Delete 4 to earn 4 points, consequently 3 is also deleted.

* Then, delete 2 to earn 2 points. 6 total points are earned.

*

* Example 2:

* Input: nums = [2, 2, 3, 3, 3, 4]

* Output: 9

* Explanation:

* Delete 3 to earn 3 points, deleting both 2's and the 4.

* Then, delete 3 again to earn 3 points, and 3 again to earn 3 points.

* 9 total points are earned.

*

* Note:

* The length of nums is at most 20000.

* Each element nums[i] is an integer in the range [1, 10000].

*/

public class DeleteAndEarn740 {

public int deleteAndEarn(int[] nums) {

if (nums == null || nums.length == 0) return 0;

int[] count = new int[10001];

int max = 0;

for (int n: nums) {

max = Math.max(max, n);

count[n]++;

}

int[] dp = new int[max + 1];

dp[0] = 0;

dp[1] = count[1];

for (int i=2; i<=max; i++) {

if (count[i] == 0) {

dp[i] = Math.max(dp[i-1], dp[i-2]);

} else {

dp[i] = Math.max(dp[i-1], dp[i-2] + count[i] * i);

}

}

return dp[max];

}

public int deleteAndEarn2(int[] nums) {

if (nums == null || nums.length == 0) return 0;

int[] count = new int[10001];

int max = 0;

for (int n: nums) {

max = Math.max(max, n);

count[n]++;

}

int dp0 = 0;

int dp1 = count[1];

for (int i=2; i<=max; i++) {

int tmp = dp1;

if (count[i] == 0) {

dp1 = Math.max(dp1, dp0);

} else {

dp1 = Math.max(dp1, dp0 + count[i] * i);

}

dp0 = tmp;

}

return dp1;

}

}