Queue

Initialize

static final int QUEUELEN=50;
    class DATA4
    {
        string name;
        int age;
    }
    class SQType
    {
        DATA4[] data = new DATA4[QUEUELEN]
        int head;
        int tail;
                
    }
    
    SQType SQTypeInit()
    {
        SQType q;
        if((q = new SQType())!=null)
        {
            q.head=0;
            q.tail=0;
            return q;
        }
        else
        {
            return null;
        }
    }

Is empty?

int SQTypeIsEmpty(SQType q)
    {
        int temp=0;
        if(q.head==q.tail)
        {
            temp=1;
            return(temp);
        }
    }

Is Full?

    int SQTypeIsFull(SQType q)
    {
        int temp=0;
        if(q.tail==QUEUELEN)
        {
            temp=1;
            return (temp);
        }
    }

Clear data

void SQTypeClear(SQType q)
    {
        q.head=0;
        q.tail=0;
    }

Free memory

    void SQTypeFree(SQType q)
    {
        if(q!=null)
        {
            q=null;
        }
    }

Add in quue

    int InSQType(SQType q,DATA4 data)
    {
        if(q.tail==QUEUELEN)
        {
            System.out.println("memory full");
            return 0;
        }
        else
        {
            q.data[q.tail++]=data;
            return 1;
        }
    }

delete in queue

    DATA4 OutSQType(SQType q)
    {
        if(q.head==q.tail) {
            System.out.println("empty queue");
            System.exit(0);
        }else
        {
            return q.data[q.head++];
        }
        return null;
    }

peek

    DATA PeekSQType(SQType q)
    {
        if(SQTypeIsEmpty(q)==1)
        {
            System.out.println("empty queue");
            return null;
        }
        else
        {
            return q.data[q.head];
        }
    }

calculate the length of queue

    int SQTypeLen(SQType q)
    {
        int temp;
        temp=q.tail-q.head;
        return(temp);
    }