1. Two Sum

1/1.cpp

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+        map<int, int> numMap;
+
+        int index = 0;
+        int currentTargetNum = 0;
+        for(; index < nums.size(); index++){
+            currentTargetNum = target - nums[index];
+            if(numMap.find(currentTargetNum) != numMap.end() && index != numMap[currentTargetNum]){
+                break;
+            }
+
+            numMap[nums[index]] = index;
+        }
+
+        return { index, numMap[currentTargetNum] };
+    }
+};

1/2.cpp

@@ -0,0 +1,18 @@
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+        map<int, int> numMap;
+
+        int index, currentTargetNum;
+        for(index = 0; index < nums.size(); index++){
+            currentTargetNum = target - nums[index];
+            if(numMap.find(currentTargetNum) != numMap.end()){
+                break;
+            }
+
+            numMap[nums[index]] = index;
+        }
+
+        return { index, numMap[currentTargetNum] };
+    }
+};

1/3.cpp

@@ -0,0 +1,17 @@
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+        map<int, int> numMap;
+        int currentOther, index;
+
+        for(index = 0; index < nums.size(); index++){
+            currentOther = target - nums[index];
+            if(numMap.find(currentOther) != numMap.end()){
+                break;
+            }
+            numMap[nums[index]] = index;
+        }
+
+        return { index, numMap[currentOther] };
+    }
+};

1/4.cpp

@@ -0,0 +1,15 @@
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+        map<int, int> numMap;
+        for(int index = 0; index < nums.size(); index++){
+            int numToFind = target - nums[index];
+            if(numMap.find(numToFind) != numMap.end()){
+                return { index, numMap[numToFind] };
+            }
+            numMap[nums[index]] = index;
+        }
+
+        return {};
+    }
+};