feat: add cpp solution to lcof2 problem: NO.006 (doocs#564)

* lcof2/剑指 Offer II 006. 排序数组中两个数字之和 cpp solution

* Update lcof2/剑指 Offer II 006. 排序数组中两个数字之和/README.md

Co-authored-by: willrlzhang <willrlzhang@tencent.com>
Co-authored-by: Yang Libin <contact@yanglibin.info>

Author: 3 people

lcof2/剑指 Offer II 006. 排序数组中两个数字之和/README.md

@@ -113,10 +113,47 @@ func twoSum(numbers []int, target int) []int {
 }
 ```
 
+### **C++**
+
+```cpp
+class Solution
+{
+    public:
+        vector<int> twoSum( vector<int> & numbers, int target )
+        {
+            int i = 0;
+            int j = numbers.size() - 1;
+            vector<int> res;
+
+            while (i < j)
+            {
+                int sum = numbers[i] + numbers[j];
+                if(sum < target)
+                {
+                    i++;
+                }
+                else if (sum > target)
+                {
+                    j--;
+                }
+                else
+                {
+                    res.push_back(i);
+                    res.push_back(j);
+                    break;
+                }
+            }
+
+            return res;
+        }
+};
+```
+
 ### **...**
 
 ```
 
 ```
 
 <!-- tabs:end -->
+

lcof2/剑指 Offer II 006. 排序数组中两个数字之和/Solution.cpp

@@ -0,0 +1,31 @@
+class Solution
+{
+    public:
+        vector<int> twoSum( vector<int> & numbers, int target )
+        {
+            int i = 0;
+            int j = numbers.size() - 1;
+            vector<int> res;
+
+            while (i < j)
+            {
+                int sum = numbers[i] + numbers[j];
+                if(sum < target)
+                {
+                    i++;
+                }
+                else if (sum > target)
+                {
+                    j--;
+                }
+                else
+                {
+                    res.push_back(i);
+                    res.push_back(j);
+                    break;
+                }
+            }
+
+            return res;
+        }
+};