PV operation daily question - orange apple question (advanced version variant)

Yesterday's advanced version still had challenges , Let's watch a variant of it today

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One 、 Problem description

There is a plate on the table , It can hold up to four fruits , Only put or take out at a time A fruit , Dad put apples on the plate , Mom put oranges on the plate ; Yes One child, one daughter , My son eats one orange at a time , My daughter eats one apple at a time . Please use semaphores and PV Operate to solve the problem .

Slightly changed ：
1. The maximum number of fruits in the buffer
2. In fact, it is simpler than the advanced version , Fruit is not required to be placed alternately

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Two 、 problem solving

：

// Compared with the previous topic , There is no need to set the semaphore for placing fruits alternately 
semaphore mutex;
semaphore empty=4;
semaphore appleCount=0;
semaphore orangeCount=0;

Father()
{
    
    while(1)
    {
    
        P(empty);
        P(mutex);
         Put in an apple ;
        V(mutex);
        V(appleCount);
    }
}

Mother()
{
    
    while(1)
    {
    
        P(empty);
        P(mutex);
         Put in an orange ;
        V(mutex);
        V(orangeCount);
    }
}

Son()
{
    
    while(1)
    {
    
        P(orangeCount);
        P(mutex);
         Take an orange ;
        V(mutex);
        V(empty);
    }
}

Daughter()
{
    
    while(1)
    {
    
        P(appleCount);
        P(mutex);
         Take an apple ;
        V(mutex);
        V(empty);
    }
}

Do you think this problem is quite simple

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3、 ... and 、 twitter

perseverance prevails ！ I like the feeling that the future is unknown , You come on ！