Adds find the median solution

Author: omonimus1

problem-solving/find-the-median.cpp

@@ -0,0 +1,17 @@
+// https://www.hackerrank.com/challenges/find-the-median/problem
+int findMedian(vector<int> arr) {
+    sort(arr.begin(), arr.end());
+
+    int len = arr.size();
+    // If number of element in the list is odd
+    // Return middle element
+    if(len % 2 != 0)
+        return arr[(len/2)];
+    
+    // Return average of the two middle elements
+    int a = arr[len/2];
+    int b = arr[(len/2)+1];
+    
+    return (a + b)/2;
+
+}