Commit 9b3fc6b

committed

solves #2815: Max Pair Sum in an Array in java

1 parent bbcc01c commit 9b3fc6bCopy full SHA for 9b3fc6b

File tree

+31

-1

lines changed

+31

-1

lines changed

Lines changed: 4 additions & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -843,4 +843,7 @@`
`843`	`843`	`\| 2788 \| [Split Strings by Separator](https://leetcode.com/problems/split-strings-by-separator) \| [![Java](assets/java.png)](src/SplitStringsBySeparator.java) \| \|`
`844`	`844`	`\| 2798 \| [Number of Employees Who Met the Target](https://leetcode.com/problems/number-of-employees-who-met-the-target) \| [![Java](assets/java.png)](src/NumberOfEmployeesWhoMetTheTarget.java) \| \|`
`845`	`845`	`\| 2806 \| [Account Balance After Rounded Purchase](https://leetcode.com/problems/account-balance-after-rounded-purchase) \| [![Java](assets/java.png)](src/AccountBalanceAfterRoundedPurchase.java) \| \|`
`846`		`-\| 2810 \| [Faulty Keyboard](https://leetcode.com/problems/faulty-keyboard) \| [![Java](assets/java.png)](src/FaultyKeyboard.java) \| \|`
	`846`	`+\| 2810 \| [Faulty Keyboard](https://leetcode.com/problems/faulty-keyboard) \| [![Java](assets/java.png)](src/FaultyKeyboard.java) \| \|`
	`847`	`+\| 2815 \| [Max Pair Sum in an Array](https://leetcode.com/problems/max-pair-sum-in-an-array) \| [![Java](assets/java.png)](src/MaxPairSumInAnArray.java) \| \|`
	`848`	`+\| 2824 \| [Count Pairs Whose Sum is Less than Target](https://leetcode.com/problems/count-pairs-whose-sum-is-less-than-target) \| [![Java](assets/java.png)](src/) \| \|`
	`849`	`+\| 2828 \| [Check if a String Is an Acronym of Words](https://leetcode.com/problems/check-if-a-string-is-an-acronym-of-words) \| [![Java](assets/java.png)](src/) \| \|`

Lines changed: 27 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,27 @@`
	`1`	`+// https://leetcode.com/problems/max-pair-sum-in-an-array`
	`2`	`+// T: O(N)`
	`3`	`+// S: O(1)`
	`4`	`+`
	`5`	`+public class MaxPairSumInAnArray {`
	`6`	`+ public int maxSum(int[] nums) {`
	`7`	`+ final int[] digitMaxSum = new int[9];`
	`8`	`+ int maxPairSum = 0;`
	`9`	`+ for (int element : nums) {`
	`10`	`+ final int maxDigit = getMaxDigit(element);`
	`11`	`+ if (digitMaxSum[maxDigit - 1] != 0) {`
	`12`	`+ maxPairSum = Math.max(maxPairSum, digitMaxSum[maxDigit - 1] + element);`
	`13`	`+ }`
	`14`	`+ digitMaxSum[maxDigit - 1] = Math.max(digitMaxSum[maxDigit - 1], element);`
	`15`	`+ }`
	`16`	`+ return maxPairSum == 0 ? -1 : maxPairSum;`
	`17`	`+ }`
	`18`	`+`
	`19`	`+ private int getMaxDigit(int number) {`
	`20`	`+ final String string = number + "";`
	`21`	`+ int maxDigit = 0;`
	`22`	`+ for (int i = 0 ; i < string.length() ; i++) {`
	`23`	`+ maxDigit = Math.max(maxDigit, string.charAt(i) - '0');`
	`24`	`+ }`
	`25`	`+ return maxDigit;`
	`26`	`+ }`
	`27`	`+}`

Comments

(0)