Problem #1
two sum
problem details
problem
1
title
two sum
short description
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.
Problem Statement
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].My solution
public class Solution {
public int[] TwoSum(int[] nums, int target) {
Dictionary<int, int> dict = new Dictionary<int, int>();
for (int i = 0; i < nums.Length; i++)
{
var diff = target - nums[i];
if (dict.ContainsKey(diff))
{
return new int[] { dict[diff], i };
}
else
{
dict[nums[i]] = i;
}
}
return null;
}
}