【Leetcode】 1. Two Sum

1.英文題目

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].

2.解題

public static int[] twoSum(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 two sum solution");
    }