源代码:
import java.util.Arrays; public class Solution { public int[] twoSum(int[] numbers, int target) { int[] results = new int[2]; int len = numbers.length; Node[] nodes = new Node[len]; for (int i = 0; i < len; i++) { nodes[i] = new Node(i + 1, numbers[i]); } /* Node tempNode = null; for (int i = 0; i < len; i++) { for (int j = 0; j < len - 1 - i; j++) { if (nodes[j].value > nodes[j + 1].value) { tempNode = nodes[j]; nodes[j] = nodes[j + 1]; nodes[j + 1] = tempNode; } } } */ Arrays.sort(nodes); int key = -1, index = -1; for (int i = 0; i < len; i++) { key = target - nodes[i].value; index = binarySearch(nodes, key); if (index != -1 && i != index) { if (nodes[i].index < nodes[index].index) { results = new int[] { nodes[i].index, nodes[index].index }; } else { results = new int[] { nodes[index].index, nodes[i].index }; } return results; } } return results; } public int binarySearch(Node[] nodes, int key) { int left = 0, right = nodes.length - 1, mid = (left + right) >> 1; while (left <= right) { mid = (left + right) >> 1; if (nodes[mid].value == key) { return mid; } else if (nodes[mid].value > key) { right = mid - 1; } else { left = mid + 1; } } return -1; } class Node implements Comparable<Node>{ int index; int value; public Node() { } public Node(int index, int value) { this.index = index; this.value = value; } @Override public int compareTo(Node node) { if (this == node) { return 0; } return this.value - node.value; } } }