structures to draw and SIMPLY explain.

#1.) Add a node to the beginning of a queue.

#2.) Add a node to the end of a queue

you can use paper and post me the image if you want.

QUEUE.C

//queue

#include

#include

#include

#include

struct entry

{

char name[81];

} part;

typedef struct LISTREC

{

struct entry info;

struct LISTREC * link;

} LISTREC;

LISTREC *top , *purgequeue(), *ne, *p, *last;

void push(), pop();

void printqueue();

void loadfile();

void countqueue();

void menu();

FILE *stream1,*stream2;

void savequeue();

void main()

{

char selection;

top = NULL;

stream1 = fopen(“data.bin”,”r+b”);

/* initialize */

loadfile();

clrscr();

for (;;) {

menu ();

selection = getche();

switch (toupper(selection))

{

case ‘1’ : push();clrscr() ; break;

case ‘2’ : pop(); clrscr() ; break;

case ‘3’ : printqueue(top) ; clrscr() ; break;

case ‘4’ : loadfile() ; clrscr() ; break;

case ‘5’ : savequeue() ; clrscr(); break;

case ‘6’ : countqueue() ; clrscr(); break;

case ‘7’ : top = purgequeue(top) ; clrscr(); break;

case ‘Q’ : clrscr() ; return ;break;

} /* switch */

} /* for */

} /* main */

void push()

{

clrscr();

gotoxy(10,12);

printf(“n name to add “);

scanf(” %[^n]”,part.name);

ne=(LISTREC *) malloc(sizeof(LISTREC));

ne->info=part;

ne->link=NULL;

if (! top) top=last=ne;

else { last->link=ne; last=ne; }

//ne->link=top;

//top=ne;

}//push

void printqueue(LISTREC *top)

{

clrscr() ;

printf (“nn”);

while (top){

printf(“n %s “, top->info.name);

top = top->link;

} /* while */

gotoxy(52,25) ; printf(“Press Any Key to Continue”) ; getch();

} /* printqueue */

void pop ()

{

clrscr();

gotoxy(10,12);

if (! top) { printf(“na the queue is empty !!!”); getch(); return;}

p=top;

top=top->link;

printf(“n %s”,p->info.name);

getch();

free(p);

} /* pop */

void loadfile ()

{

int n;

rewind(stream1);

for(;;) {

n=fread(&part,sizeof(part),1, stream1);

if (!n) break;

ne=(LISTREC *) malloc(sizeof(LISTREC));

ne->info=part; ne->link=NULL;

if (! top) top=last=ne;

else { last->link=ne; last=ne; }

}//for

}//loadfile

void savequeue ()

{

stream2 = fopen(“output.bin”,”w+b”);

p = top;

while (p)

{

fwrite(&p->info,sizeof(part),1,stream2);

// fprintf(stream2,”n %s”,p->info.name);

p=p->link;

}

fclose(stream2);

}

void countqueue ()

{

int i = 0;

p = top;

while (p)

{

i++;

p=p->link;

}

clrscr() ; gotoxy(27,12) ;

printf(“Total Items in queue – %d”,i);

gotoxy(52,25) ; printf(“Press Any Key to Continue”);

getch();

}

void menu ()

{

gotoxy(30,1) ; printf(“NORTHEASTERN UNIVERSITY”);

gotoxy(32,2) ; printf (“University College”);

gotoxy(37,3) ; printf (“MIS 4277”);

gotoxy(19,9) ; printf (” 1 – Add an Item to the queue “);

gotoxy(19,10) ; printf (” 2 – Delete an Item from the queue “);

gotoxy(19,11) ; printf (” 3 – List the queue from Top to Bottom “);

gotoxy(19,12) ; printf (” 4 – Load File to Current queue “);

gotoxy(19,13) ; printf (” 5 – Save Current queue in File OUTPUT.BIN “);

gotoxy(19,14) ; printf (” 6 – Count Number of Items in queue “);

gotoxy(19,15) ; printf (” 7 – Purge the Entire queue “);

gotoxy(19,16) ; printf (” Q – End the program “);

gotoxy(25,22) ; printf (“Please enter your selection – “);

}

LISTREC *purgequeue (LISTREC *top)

{

p = top;

while (p)

{

top = top->link;

free(p);

p=top;

} /* while */

clrscr() ; gotoxy(27,12) ; printf(“queue has been Purged”);

gotoxy(52,25) ; printf(“Press Any Key to Continue -“) ; getch();

return (top);

} /* purgequeue */