https://wordpress.diguage.com/archives/112.html 分享技术带来的喜悦—https://www.diguage.com/ Thu, 11 Jun 2020 02:02:48 +0000 hourly 1 http://wordpress.org/?v=3.4.2 https://wordpress.diguage.com/archives/112.html#comment-22898 leetcode-java题解（每天更新） | MoonSky Mon, 09 Mar 2015 04:19:49 +0000 http://www.diguage.com/?p=112#comment-22898 [...] 思路：既然题目假设有两个数a,b肯定相加得到目标值c，那么肯定有c-a存在于数组中，于是问题转化成了如何高效检查一个数组中是否包含某个值，在这里找到一些答案http://www.diguage.com/archives/112.html。于是采用先排序，然后用Arrays.binarySearch的方法，然后根据OJ提示的一些错误，修改几下就好了。具体代码如下，254ms，和九章以及其他解题答案不太一样。 Source code   import java.util.Arrays;   public class Solution1 { public static int[] twoSum(int[] numbers, int target) { int[] num = numbers.clone(); Arrays.sort(num); int size = num.length; int[] answers = new int[2]; for(int i=0;i<size;i++) { if(Arrays.binarySearch(num, target-num[i])>0) { int count=0,index1 = 0,index2=0; for(int j=0;j<size;j++) { if(numbers[j]==num[i]||numbers[j]==target-num[i]) { count++; if(count==2) { index2=j; answers[0] = (index1<index2?index1:index2)+1; answers[1] = (index1>index2?index1:index2)+1; break; } else { index1=j; }   } }     } } return answers; } public static void main(String[] args) { int[] test = {-3,4,3,90}; int target = 0; int[] result = {0,0}; result = twoSum(test,target); System.out.println(result[0]+","+result[1]); } } [...] [...] 思路：既然题目假设有两个数a,b肯定相加得到目标值c，那么肯定有c-a存在于数组中，于是问题转化成了如何高效检查一个数组中是否包含某个值，在这里找到一些答案http://www.diguage.com/archives/112.html。于是采用先排序，然后用Arrays.binarySearch的方法，然后根据OJ提示的一些错误，修改几下就好了。具体代码如下，254ms，和九章以及其他解题答案不太一样。 Source code   import java.util.Arrays;   public class Solution1 { public static int[] twoSum(int[] numbers, int target) { int[] num = numbers.clone(); Arrays.sort(num); int size = num.length; int[] answers = new int[2]; for(int i=0;i<size;i++) { if(Arrays.binarySearch(num, target-num[i])>0) { int count=0,index1 = 0,index2=0; for(int j=0;j<size;j++) { if(numbers[j]==num[i]||numbers[j]==target-num[i]) { count++; if(count==2) { index2=j; answers[0] = (index1<index2?index1:index2)+1; answers[1] = (index1>index2?index1:index2)+1; break; } else { index1=j; }   } }     } } return answers; } public static void main(String[] args) { int[] test = {-3,4,3,90}; int target = 0; int[] result = {0,0}; result = twoSum(test,target); System.out.println(result[0]+","+result[1]); } } [...]

]]>