C ++中的初学者“ while”程序

Question

I have to solve a problem where I calculate the salary of employees where they get 10 euros per hour for the first 40 hours and then every additional hour they get 15 euros. I have solved the problem but my console prints the answer in an endless loop and I don't know where I am wrong.

int hours;
double salary;

int main()
{

    cout << "Enter amount of hours worked" << endl;
    cin >> hours;

    while (hours <= 40)
    {
        salary = hours * 10;
        cout << "Salary of the employee is: " << salary << endl;
    }

    while (hours > 40)
    {
        salary = (40 * 10) + (hours - 40) * 15;
        cout << "Salary of the employee is: " << salary << endl;
    }

    system("pause");
    return 0;
}

Answer 1

Change your while s to if s.

The condition inside while would be always true , because hours will always be less than 40, as no modification of hours inside the while condition hence resulting in an infinite loop .

Modified code:

int hours;
double salary;

int main()
{

    cout << "Enter amount of hours worked" << endl;
    cin >> hours;

    if (hours <= 40)
    {
        salary = hours * 10;
        cout << "Salary of the employee is: " << salary << endl;
    }
    else //I have removed the condition because if hours is not less than 40,
        // it has to be greater than 40!
    {
        salary = (40 * 10) + (hours - 40) * 15;
        cout << "Salary of the employee is: " << salary << endl;
    }

    system("pause");
    return 0;
}

A solution using while loops.

Since you are hell bent on getting a while loop solution,

Code:

int hours;
int counthour = 0;
double salary;

int main()
{

    cout << "Enter amount of hours worked" << endl;
    cin >> hours;

    while (counthour <= hours)
    {
        if(counthour <= 40)
            salary += 10;
        else
            salary += 15;
        counthour++;

    }
    cout << "Salary of the employee is: " << salary << endl;
    system("pause");
    return 0;
}

Answer 2

In order for the following loop to not be infinite

while (hours <= 40)
{
    salary = hours * 10;
    cout << "Salary of the employee is: " << salary << endl;
}

Something in the loop is going to have to modify hours in a way that will cause hours <= 40 to be false .

right now, only salary is getting modified in that loop.

Answer 3

You're using while loops like they're if statements, kind of.

Use two variables, one to take the amount of hours worked and one to start at 0 and count each hour paid.

int hours;
int hourscounted = 0;
double salary;

int main()
{

    cout << "Enter amount of hours worked" << endl;
    cin >> hours;

    while (hourscounted  <= hours)
    {
        if(hourscounted < 40)
        {
            salary = salary + 10;
        }
        else
        {
            salary = salary + 15;
        }
        hourscounted++;

    }
    cout << "Salary of the employee is: " << salary << endl;
    system("pause");
    return 0;
}

Answer 4

Change while to if :P And tip for future - do not use endl, unless you really need to do it. And you can have printing (cout) outside of loop/if-statement. It will never end, the while loop, it depends on something, that is not changed.

Answer 5

EDIT: After reading your code and problem in more detail, it seems you should replace while by if to satisfy the logic you are looking at.

If your code prints in an endless loop, you should always check that why the conditions for its termination are not being met.

In your case, your loops terminate when hours < 40 (1st case) and hours > 40 (2nd case). You are not modifying hours in the loop, and so it is stuck in an infinite cycle.