实验二

#include<iostream>
using namespace std;
struct complex {
 double real;
 double imaginary;
};
int add(int a, int b)
{
 return a + b;
}
double add(double a, double b)
{
 return a / b;
}
complex add(complex a, complex b)
{
 complex s;
 s.imaginary = a.imaginary + b.imaginary;
 s.real = a.real + b.real;
 return s;
}
int main()
{
 complex a = { 2.3,3.2 };
 complex b = { 4.5,5.4 };
 complex c = add(a, b);
 cout << "1+2=" << add(1, 2) << endl;
 cout << "2.2/1.1=" << add(2.2, 1.1) << endl;
 cout << "complex ab=" << c.real << "," << c.imaginary << endl;
 system("pause");
 return 0;
}

 #include<iostream>
using namespace std;
template<class X>
X Quicksort(X a[], int low, int high)
{
 if (low >= high)
 {
  return 0;
 }
 int x = low;
 int y = high;
 int key = a[x];
 while (x < y)
 {
  while (a[y] >= key && x < y)
  {
   --y;
  }
  a[x] = a[y];
  while (a[x] <= key && x < y)
  {
   ++x;
  }
  a[y] = a[x];
 }
 a[x] = key;
 Quicksort(a, low, x - 1);
 Quicksort(a, x + 1, high);
}
int main()
{
 int i, a[5] = { 1,6,2,9,5 };
 Quicksort(a, 0, 5);
 for (i = 1; i < 6; i++)
  cout << a[i] << " ";
 system("pause");
 return 0;
}

#include <iostream>
#include <string>
using namespace std;
class User {
public:
 void setinfo(string name1 = "", string passwd1 = "12345", string email1 = "");
 void changepasswd();
 void printinfo();
private:
 string name;
 string passwd;
 string email;
};
void User::setinfo(string name1, string passwd1, string email1) {
 name = name1;
 passwd = passwd1;
 email = email1;
}
void User::changepasswd() {
 string old;
 int i = 0;
 do {
  cout << "请输入原密码:";
  cin >> old;
  if (old == passwd)
  {
   cout << "请输入修改后的密码:";
   cin >> passwd;
   cout << "修改成功!";
   break;
  }
  else    i++;
  if (i == 3)
   cout << "连续三次输错，请稍后重试！";
 } while (i != 3);
}
void User::printinfo() {
 cout << "name: " << name << endl;
 cout << "password:******" << endl;
 cout << "email: " << email << endl;
}
int main() {
 cout << "testing 1......" << endl;
 User user1;
 user1.setinfo("Leonard");
 user1.printinfo();
 user1.changepasswd();
 user1.printinfo();
 cout << "testing 2......" << endl;
 User user2;
 user2.setinfo("Jonny", "92197", "xyz@hotmail.com");
 user2.printinfo();
 system("pause");
 return 0;
}