From 4d731f440cf29dde8acd97931c0ff74e96d81349 Mon Sep 17 00:00:00 2001
From: Luke Else <mail@luke-else.co.uk>
Date: Thu, 20 Oct 2022 07:52:34 +0100
Subject: [PATCH] Updated two sum to work with Hashmap

---
 C++/src/1. Two Sum/TwoSum.cpp | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/C++/src/1. Two Sum/TwoSum.cpp b/C++/src/1. Two Sum/TwoSum.cpp
index 7da6bcb..8dcd10b 100644
--- a/C++/src/1. Two Sum/TwoSum.cpp	
+++ b/C++/src/1. Two Sum/TwoSum.cpp	
@@ -1,4 +1,5 @@
 #include <vector>
+#include <map>
 
 using namespace std;
 
@@ -6,17 +7,20 @@ namespace TwoSum{
     class Solution {
     public:
         vector<int> twoSum(vector<int>& nums, int target) {
+            vector<int> res;
+            map<int, int> hashMap;
             for (int i = 0; i < nums.size(); i++)
-            {
-                for (int j = i+1; i < nums.size(); j++)
-                {//Loop through the dataset
-                    if (nums[i] + nums[j] == target)
-                    {//Check sum
-                        return vector<int>() = {i, j};
-                    }
+            {//Loop through Dataset
+                if (hashMap.find(target - nums[i]) != hashMap.end())
+                {//See if the remaining value is in the map
+                    res.push_back(i);
+                    res.push_back(hashMap[target - nums[i]]);
+                    return res;
                 }
+                else
+                    hashMap.emplace(nums[i], i);
             }
-            return vector<int>();
+            return res;
         }
     };
 }
\ No newline at end of file