LeetCode 1 Two Sum (hash)

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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].

题目链接：https://leetcode.com/problems/two-sum/

2ms，时间击败99.62%

class Solution {
    public int[] twoSum(int[] nums, int target) {
        HashMap<Integer, Integer> mp = new HashMap<>();
        int x = 0, y = 0;
        for (int i = 0; i < nums.length; i++) {
            int tmp = target - nums[i];
            if (mp.containsKey(tmp)) {
                x = mp.get(tmp);
                y = i;
                break;
            }
            mp.put(nums[i], i);
        }
        return new int[] {x, y};
    }
}