ARTS 第1周

package org.nocoder.leetcode.solution;

/**
 * 1.Two Sum 
 * Given an array of integers, return indices of the two numbers such that they add up to a specific target.
 * You may assume that each input would have exactly one solution, and you may not use the same element twice.
 * 
 * Example:
 * Given nums = [2, 7, 11, 15], target = 9,
 * Because nums[0] + nums[1] = 2 + 7 = 9,
 * return [0, 1].
 *
 * @author jason
 * @date 18/7/6.
 */
public class TwoSumSolution {

    public static int[] twoSum1(int[] nums, int target) {
        for (int i = 0; i < nums.length; i++) {
            for (int j = i + 1; j < nums.length; j++) {
                if ((nums[i] + nums[j]) == target) {
                    return new int[]{i, j};
                }
            }
        }
        throw new IllegalArgumentException("No solution!");
    }
    
    public static int[] twoSum2(int[] nums, int target){
        Map<Integer, Integer> resultMap = new HashMap<>();
        for (int i = 0; i < nums.length; i++) {
            int result = target - nums[i];
            if(resultMap.containsKey(result)){
                return new int[]{resultMap.get(result), i};
            }
            resultMap.put(nums[i], i);
        }
        throw new IllegalArgumentException("No solution!");
    }
}

<resources>
    <resource>
        <directory>src/main/java</directory>
        <includes>
            <include>**/*.xml</include>
        </includes>
    </resource>
</resources>