52 lines
1.7 KiB
Java
52 lines
1.7 KiB
Java
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package com.zerroi.leetcode.Three12;
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import java.util.Arrays;
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/*
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* 给你一个下标从 1 开始的整数数组 numbers ,该数组已按 非递减顺序排列 ,请你从数组中找出满足相加之和等于目标数 target 的两个数。如果设这两个数分别是 numbers[index1] 和 numbers[index2] ,则 1 <= index1 < index2 <= numbers.length 。
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以长度为 2 的整数数组 [index1, index2] 的形式返回这两个整数的下标 index1 和 index2。
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你可以假设每个输入 只对应唯一的答案 ,而且你 不可以 重复使用相同的元素。
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你所设计的解决方案必须只使用常量级的额外空间。
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* */
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public class TwoSum {
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public static void main(String[] args) {
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SolutionSecond solutionSecond = new SolutionSecond();
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int[] res = solutionSecond.twoSum(new int[]{2, 7, 11, 15}, 9);
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for (int i : res) {
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System.out.println("i = " + i);
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}
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}
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}
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class SolutionSecond {
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public int[] twoSum(int[] numbers, int target) {
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for (int i = 0; i < numbers.length; i++) {
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for (int j = i + 1; j < numbers.length; j++) {
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if (numbers[i] + numbers[j] == target) {
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return new int[]{i+1, j+1};
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}
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}
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}
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return null;
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}
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public int[] twoSum(int[] numbers, int target, int abc) {
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int left = 0;
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int right = numbers.length - 1;
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while (left < right) {
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int sum = numbers[left] + numbers[right];
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if (sum == target) {
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return new int[]{left + 1, right + 1};
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} else if (sum > target) {
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right--;
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} else {
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left++;
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}
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}
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return null;
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}
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}
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