<>167. Sum of two numbers II - Input ordered array

<> Given one is in ascending order Ordered array of , Find two numbers so that their sum equals the target number .

<> The function should return these two subscript values index1 and index2, among index1 Must be less than index2.

<> explain :

<> The returned subscript value (index1 and index2) It's not starting from scratch .

<> You can assume that each input corresponds to only one answer , And you can't reuse the same elements .

<> Examples :

<> input : numbers = [2, 7, 11, 15], target = 9

<> output : [1,2]

<> explain : 2 And 7 The sum is equal to the target number 9 . therefore index1 = 1, index2 = 2 .

<> Method 1 : The double loop judges whether it is equal one by one , Get the corresponding index .
public static int[] twoSum(int[] numbers, int target) { int[] index = new int[2
]; for (int i = 0; i < numbers.length; i++) { for (int j = i + 1; j < numbers.
length; j++) { if (numbers[i]+numbers[j]==target){ index[0] = i+1; index[1] = j+
1; } } } return index; }
<> Method 2 : Double pointer , According to the sum result and the size of the target value to determine whether the index is forward or backward
public static int[] twoSum(int[] numbers, int target) { // Double pointer int left = 0;
int right = numbers.length - 1; while (left < right) { int sum = numbers[left] +
numbers[right]; if (sum == target) { return new int[]{left + 1, right + 1}; }
else if (sum > target) { right--; } else { left++; } } return new int[2]; }

Technology
©2019-2020 Toolsou All rights reserved,
SQL Server Database Glossary CSS Animation effect dedecms Website is hacked How to solve hijacking to other websites Count the number of letters (java Language implementation )Java Basics ( Three ) String In depth analysis The difference between static method and non static method And storage location Django Personal blog building tutorial --- Time classified archiving Keras Save and load model (JSON+HDF5)hive Summary of processing methods for a large number of small files Website mobile phone number capture method