#include <iostream>
using namespace std;
int main () {
int*ptr = NULL;
cout << "The value of ptr is " << ptr ;
#include <iostream>
using namespace std;
int main () {
intvar = 20;// actual variable declaration.
//
#include <iostream>
using namespace std;
int main () {
intvar1;
char var2[10];
cout << "Address of var1 variable: ";
#include <iostream>
#include <string>
using namespace std;
int main () {
string str1 = "Hello";
#include <iostream>
#include <cstring>
using namespace std;
int main () {
char str1[10] = "Hello";
#include <iostream>
using namespace std;
int main () {
char greeting[6] = {'H', 'e', 'l', 'l', 'o', '\\0'};
#include <iostream>
#include <ctime>
using namespace std;
// function to generate and retrun random numbers.
#include <iostream>
using namespace std;
double getAverage(int arr[], int size) {
int i, sum = 0;
double avg;
#include <iostream>
using namespace std;
int main () {
// an array with 5 elements.
double balance[5] = {1000.0, 2.0, 3.4, 17.0, 50.0};
#include <iostream>
using namespace std;
int main () {
// an array with 5 rows and 2 columns.
int a[5][2] = { {0,0}, {1,2}, {2,4}, {3,6},{4,8}};
#include <iostream>
using namespace std;
#include <iomanip>
using std::setw;
int main () {
int n[ 10 ];// n is an array of 10 integers
#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;
int main () {
#include <iostream>
#include <cmath>
using namespace std;
int main () {
// number definition:
#include <iostream>
using namespace std;
int main () {
// number definition:
shorts;
inti;
longl;
floatf;
#include <iostream>
using namespace std;
// function definition to swap the values.
void swap(int &x, int &y) {
#include <iostream>
using namespace std;
// function definition to swap the values.
void swap(int *x, int *y) {
#include <iostream>
using namespace std;
void swap(int x, int y) {
int temp;
temp = x; /* save the value of x */
#include <iostream>
using namespace std;
int sum(int a, int b = 20) {
int result;
result = a + b;
return (result);
// 标准输入流
#include <iostream>
using namespace std;
int main() {
char name[50];
cout << "Please enter your name: ";
// C++标准输出流
#include <iostream>
using namespace std;
int main() {
char str[] = "Hello C++";
#include <iostream>
#include <ctime>
using namespace std;
int main() {
// current date/time based on current system
#include <iostream>
#include <ctime>
using namespace std;
int main() {
// current date/time based on current system
#include <iostream>
#include <ctime>
using namespace std;
double vals[] = {10.1, 12.6, 33.1, 24.1, 50.0};
#include <iostream>
using namespace std;
// function declaration
void swap(int& x, int& y);
#include <iostream>
using namespace std;
int main () {
// declare simple variables
inti;
double d;
// declare reference variables
#include <iostream>
#include <ctime>
using namespace std;
// function to generate and retrun random numbers.
#include <iostream>
using namespace std;
// function declaration:
double getAverage(int *arr, int size);
#include <iostream>
#include <ctime>
using namespace std;
void getSeconds(unsigned long *par);
#include <iostream>
using namespace std;
int main () {
intvar;
int*ptr;
int**pptr;
var = 3000;
// take the address of var
#include <iostream>
using namespace std;
const int MAX = 4;
int main () {
char *names[MAX] = { "Zara Ali", "Hina Ali", "Nuha Ali", "Sara Ali" };
