Added C++ files that demonstrates the use of subtraction in C++.

Author: LawrenceQuarshie

09.cpp

@@ -0,0 +1,9 @@
+#include <iostream>
+using namespace std;
+
+int main() {
+    int x = 5;
+    int y = 3;
+    cout << x - y;
+    return 0;
+}