add intro

CPlusPlus/intro/functions.cpp

@@ -0,0 +1,38 @@
+#include "functions.h"
+#include <iostream>
+
+using namespace std;
+
+void functionF()
+{
+}
+
+void printArray(int numbers[], size_t count)
+{
+	for (size_t i = 0; i < count; i++)
+	{
+		cout << numbers[i] << " ";
+	}
+	cout << endl;
+}
+
+void changeInt(int n)
+{
+	cout << "addr of n: " << &n << endl;
+	n *= 10;
+}
+
+void changeIntPointer(int* pN)
+{
+	if (pN == nullptr) return;
+
+	cout << "addr of pN: " << &pN << endl;
+	cout << "pN: " << pN << endl;
+	*pN *= 10;
+}
+
+void changeIntReference(int& n)
+{
+	cout << "addr of n: " << &n << endl;
+	n *= 10;
+}