Create Single_Number.cc

Author: iphkwan

Single_Number.cc

@@ -0,0 +1,11 @@
+class Solution {
+public:
+    int singleNumber(int A[], int n) {
+        // Note: The Solution object is instantiated only once and is reused by each test case.
+        int ret = 0;
+        for (int i = 0; i < n; i++) {
+            ret ^= A[i];
+        }
+        return ret;
+    }
+};