在这种情况下如何添加计数器？ [关闭]

Question

编程新手。我做了一个简单的程序来读取银行密码，但我得到了一个无限循环。我知道我应该添加一个计数器，因为这是我的老师所说的，但我不知道如何实际实现它。如果有人可以提供帮助，那就太棒了。

#include <iostream>
using namespace std; 

int main() {
  int pin = 12345;
  int input;
  

  cout << "Please enter your pin." << endl;
  cin >> input;
  while (input != 12345) {
    cout << "INCORRECT PIN. TRY AGAIN." << endl;
    cout << "Please enter your pin." << endl;

    

  }
  else if (input==12345) {
    cout << "ACCESS GRANTED. WELCOME TO YOUR BANK" << endl;
  }

 return 0;
} 

Answer 1

您不会在 while 循环中再次接受输入。这就是它运行无限循环的原因。 试试这个

int main() {
  int pin = 12345;
  int input;
  

  cout << "Please enter your pin." << endl;
  cin >> input;
  while (input != pin) {
    cout << "INCORRECT PIN. TRY AGAIN." << endl;
    cout << "Please enter your pin." << endl;
    cin >> input;
  }
  if (input==pin) {
    cout << "ACCESS GRANTED. WELCOME TO YOUR BANK" << endl;
  }

 return 0;
} 

如果你想要一些计数器，比如用户输入错误密码超过 3 次，你不应该让他访问银行账户。

int main() {
  int pin = 12345;
  int input;
  const int times = 3;
  int counter = 0;

  do{
    cout << "Please enter your pin." << endl;
    cin >> input;
    if(input != pin){
       cout << "INCORRECT PIN. TRY AGAIN." << endl;
       counter++;
    } else {
       break;
    }
    if(counter == times){
        cout << "You cannot access your account. You enter wrong pin for 3 times\n";
        return 0;
    }
  }while(input != pin);
  if (input==pin) {
    cout << "ACCESS GRANTED. WELCOME TO YOUR BANK" << endl;
  }

 return 0;
}