Merge pull request #143 from rsenwar/patch-6

Update Happy_number.cpp

Happy_number.cpp

@@ -2,6 +2,7 @@
   and this sum turns out to be 1 */
 #include <iostream>
 using namespace std;
+
 int main()
 {
   int n,k,s=0,d;
@@ -23,4 +24,5 @@ int main()
    cout << n << " is a happy number" << endl;
   else
    cout << n << " is not a happy number" << endl;
+  return 0;
 }