如何計算在Sentinel Loop c中輸入了多少次輸入

Question

這是有關編程問題的詳細鏈接。 我已經完成了源代碼，但是我不知道如何計算和顯示在sendinel循環中輸入了多少次輸入。 這是我的源代碼：

#include <iostream>

using namespace std;

int main() {
  int i, hours;
  int tot_clients = 0;
  float charges;
  float tot_collection = 0;
  const int sentinel = -1;

  cout << "Welcome to ABC Parking Services Sdn Bhd" << endl;
  cout << "=======================================" << endl;

  while (hours != sentinel) {
    cout << "Please enter number of parking hours (-1 to stop)" << endl;
    cin >> hours;

    if (hours <= 2 && hours > 0) {
      charges = 1.00 * hours;
      cout << "Charges: " << charges << endl;
    }
    else if (hours > 2 && hours <= 12) {
      charges = (1.00 * 2) + ((hours - 2) * 0.50);
      cout << "Charges: " << charges << endl;
    }
    else if (hours > 12) {
      charges = 10.00 * hours;
      cout << "Charges: " << charges << endl;
    }
    else if (hours == sentinel) {
      break;
    }

    tot_collection = tot_collection + charges;
  }

  cout << "SUMMARY OF REPORT" << endl;
  cout << "=======================================" << endl;

  cout << "Total clients:" << tot_clients << endl;
  cout << "Total colletion:" << tot_collection << endl;

  return 0;
}

希望有人可以幫助我解決這個問題。 我正在為我的編程期末考試而學習。

Answer 1

我了解您想計算客戶數量（tot_clients）。 您已經初始化了tot_clients =0。這很好。 您只需要在while循環（tot_clients ++）內增加tot_clients變量。

while (hours != sentinel)
{
    cout << "Please enter number of parking hours (-1 to stop)" << endl;
    cin >> hours;

    tot_clients++; //this is the code to be added

    /*rest of the code remains same*/

Answer 2

添加tot_clients++; 在tot_collection = tot_collection + charges;之前或之后tot_collection = tot_collection + charges;

Answer 3

1-初始化小時= 0，否則在while循環的首次條件檢查期間，小時將具有一些不確定的值。
2-i假設tot_clients存儲總計 比，您只需要在每次迭代中增加tot_clients

 #include <iostream>
    using namespace std;
    int main()
    {
    int i, hours=0;
    int tot_clients=0;
    float charges;
    float tot_collection=0;
    const int sentinel = -1;

    cout << "Welcome to ABC Parking Services Sdn Bhd" << endl;
    cout << "=======================================" << endl;

    while (hours != sentinel)
    {
    cout << "Please enter number of parking hours (-1 to stop)" << endl;
    cin >> hours;`

    if (hours <= 2 && hours >0)
    {
        charges = 1.00 * hours;
        cout << "Charges: " << charges << endl;
    }

    else if (hours>2 && hours <=12)
    {
        charges = (1.00*2) + ((hours - 2) * 0.50);
        cout << "Charges: " << charges << endl;         
    }

    else if (hours > 12)
    {
        charges = 10.00 * hours;
        cout << "Charges: " << charges << endl;         
    }

    else if (hours == sentinel)
    {
        break;
    }

    tot_collection = tot_collection + charges;  
    tot_clients=tot_clients+1; //increment's on each iteration except on input -1

}


cout << "SUMMARY OF REPORT" << endl;
cout << "=======================================" << endl;

cout << "Total clients:" << tot_clients << endl;
cout << "Total colletion:" << tot_collection << endl;

return 0;

}

`