hostel.c

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<conio.h>
#define MAXCHAR 1000
int absent[100],present[100],Qblock_1bed[10],Qblock_2bed[10][10],num=12;
float grp_topper=0;
// Hash table is used to map the student details(key) to its slot/class(value).
// Collision will occur since there are two slots, which is resolved through chaining.
struct hash *cse_branch=NULL;
struct hash *ece_branch=NULL;
struct hash *mech_branch=NULL;

struct node              // Structure for student details
{
    int rollno;
    float cgpa;
    float ncgpa;
    int rank;
    char name[100];
    struct node *next;
}*current,*temp,*last=NULL,*p;

struct hash
{
    int count;
    float highest;
    struct node *head;
};

struct node *createnode(int rollno, char *name, float cgpa)
{
    struct node *newnode;
    newnode=malloc(sizeof(struct node));
    newnode->rollno=rollno;
    newnode->cgpa=cgpa;
    newnode->ncgpa=0;
    newnode->rank=0;
    strcpy(newnode->name,name);
    newnode->next=NULL;
    return newnode;
};

void insert(struct hash *branch, int rollno, char *name, float cgpa, int x)
{
    int index=x;
    struct node *newnode = createnode(rollno, name, cgpa);
    if((int)branch[index].head==0)
    {
        branch[index].head=newnode;
        branch[index].count=1;
        current=newnode;
    }
    else
    {
        current=branch[index].head;
        if(newnode->cgpa > current->cgpa)
        {
            newnode->next=current;
            branch[index].head=newnode;
            return;
        }
        else
        {
            while(current!=NULL)
            {
                if(newnode->cgpa <= current->cgpa)
                {
                    p=current;
                    current=current->next;
                }
                else
                    break;
            }
            newnode->next=p->next;
            p->next=newnode;
            branch[index].count++;
        }
    }
}

int search_details(struct hash *branch, int rno)
{
    int i,j;
    struct node *search;
    for(i=1;i<=2;i++)
    {
        search=branch[i].head;
        if(!search)
            return 0;
        while(search!=NULL)
        {
            if(search->rollno==rno)
            {
                printf("Roll No : %d\nName : %s\nCGPA : %.2f\n",search->rollno,search->name,search->cgpa);
                return 1;
            }
            search=search->next;
        }
    }
    return 0;
}

// Calculate NCGPA of the students.
void NCGPA(struct hash *branch)
{
    struct node *class_topper;
    struct node *student;
    for(int i=0;i<=2;i++)
    {
        class_topper=branch[i].head;
        student=branch[i].head;
        while(student!=NULL)
        {
            student->ncgpa=(student->cgpa*grp_topper)/branch->highest;
            student=student->next;
        }
    }
}

void display(struct hash *branch)
{
    struct node *m;
    int i;
    for(i=1;i<=2;i++)
    {
        if(branch[i].count==0)
            continue;
        m = branch[i].head;
        printf("\n Students in Slot %d of branch:\n",i);
        printf("ROLL NO  \t  NAME             CGPA\n");
        while(m!=NULL)
        {
            printf("  %d\t\t%-15s\t%10f\n",m->rollno,m->name,m->cgpa);
            m=m->next;
        }
    }
}

void topper(struct hash *branch, char p[])
{
    struct node *z;
    branch->highest=branch[1].head->cgpa;
    z=branch[2].head;
    if(branch->highest < z->cgpa)
    {
        branch->highest=z->cgpa;
        z=branch[1].head;
    }
    printf("%s branch topper is :\nROLL NO: %d\nCGPA: %f\n",p,z->rollno,branch->highest);
    if(grp_topper<branch->highest)
    {
        grp_topper=branch->highest;
    }
}

void displaylist(struct node *disp)
{
    printf("    ROLL NO       NAME                 CGPA          NCGPA\n");
    printf("----------------------------------------------------------------\n");
    while(disp!=NULL)
    {
        printf("%8d\t%-15s%15f%15f\n",disp->rollno,disp->name,disp->cgpa,disp->ncgpa);
        disp=disp->next;
    }
}
//using merge sort to sort the NCGPA list
struct node* merge(struct node* temp1, struct node* temp2)
{
    struct node* mergelist= NULL;
  	mergelist=(struct node*)malloc(sizeof(struct node));

    if (temp1 == NULL)
        return(temp2);
    else if (temp2 == NULL)
        return(temp1);
    if ( temp1->ncgpa >= temp2 ->ncgpa)
    {
        mergelist=temp1;
     	mergelist->next=merge(temp1->next, temp2);
    }
    else
    {
        mergelist=temp2;
        mergelist->next=merge(temp1,temp2->next);
    }
    return(mergelist);
}

struct node* ncgpalist(struct hash *hashtable)
{
    NCGPA(hashtable);
	return merge(hashtable[1].head, hashtable[2].head);
}

void mergeall (struct node* branch1, struct node* branch2, struct node* branch3)
{
    printf("\n\n   FINAL NCGPA LIST: \n\n");
    last=merge(merge(branch1, branch2), branch3);
 	displaylist(last);
}

int printlist()
{
 	struct node *ptr=last;
 	int x, rank=1;
 	if (ptr==NULL)
 	{
 	 	printf("\n\n  SERVER ERROR !!");
 	 	exit(0);
 	}
 	printf("\n\n\tRANK    ROLL NO     NCGPA\n");
 	printf("-------------------------------------\n");
 	while (ptr!=NULL)
 	{
 	 	ptr->rank=rank;
 	 	printf("\n\t%d",ptr->rank);
        printf("\t  %d",ptr->rollno);
        printf("\t  %f",ptr->ncgpa);
 	 	ptr=ptr->next;
        rank++;
 	}
    return rank;
}
//students are given tokens according to ranks obtained
//queue data structure is used, based on FIFO,
void tokenlist()
{
 	int i=1;
 	struct node *current= NULL;
 	printf("\n\nThe student rankers taking part in counselling are: \n");
    current=last;
 	while (current!=NULL)
 	{
 	 	present[i++]=current->rank;
        current=current->next;
    }
 	i=1;
 	while(present[i]!=0)
 	{
 	 	printf(" %d\n",present[i++]);
 	}
}

int findstudent(int arank)
{
 	struct node *prev=NULL;
    struct node *current=NULL;
    struct node *temp=NULL;
    current=last;
 	while (current!=NULL)
 	{
 	 	if (current->rank==arank)
 	 	{
 	 	 	prev->next=current->next;
            temp=current;
 	 	 	current=current->next;
            free(temp);
 	 	 	return 1;
 	 	}
 	 	else
 	 	{
 	 	 	prev=current;
 	 	 	current=current->next;
 	 	}
 	}
 	return 0;
}

void registration(int totalstud)
{
    struct node* prev=NULL;
    struct node* current=NULL;
 	current=last;
 	int i=1, absentrank=0;
    printf("\nTotal students is: %d", totalstud-1);
 	printf("\nEnter the rankers not attending counselling: ");
 	while (i<=totalstud && absentrank!=-1)
 	{
 	 	scanf("%d", &absentrank);
 	 	if (absentrank==-1)
 	 	 	i=totalstud+1;
 	 	else
 	 	{
 	 	 	if (findstudent(absentrank))
 	 	 	 	absent[i++]=absentrank;
 	 	 	else
 	 	 	 	printf("\n Roll No not found. Enter again or enter -1 to finish.\n");
 	 	}
 	}
 	i=1;
 	printf("\nSo, the ranks not attending counselling are: ");
 	while (i<=100)
 	{
 	 	if (absent[i]!=0)
 	 	 	printf("%d ", absent[i++]);
 	 	else if (absent[i]==0)
 	 	 	goto v;
 	}
 	v:  tokenlist();
}

int searchroommate(int rank)
{
 	int i=1,found=0;
 	while (absent[i]!=0)
 	{
 	 	if (absent[i]==rank)
 	 	{
 	 	 	found=1;
 	 	 	absent[i]=-1;
 	 	 	break;
 	 	}
 	 	if ((absent[i]==0 || absent[i]==-1) && !(0<absent[i]<30))
 	 	 	found=-1;
 	 	i++;
 	}
 	return found;
}

int chooseroom(int choice, int front)
{
 	int i=0, allot=0, found=0, roommaterank;
 	if (choice==1)
 	{
 	 	for (i=0; i<10; i++)
 	 	{
 	 	 	if (Qblock_1bed[i]==0)
 	 	 	{
 	 	 	 	Qblock_1bed[i]=front;
 	 	 	 	printf("CONGRATULATIONS !! Student Rank %d has been alloted 1 bed AC room in Q block.",present[front]);
                allot=1;
 	 	 	 	break;
 	 	 	}
 	 	}
 	 	if (allot==0)
 	 	 	printf("\nSorry, Q Block is full.");
 	}
    if (choice==2)
    {
	 	z:
 	 	printf("Enter NCGPA rank of roommate: ");
 	 	scanf("%d", &roommaterank );
 	 	found=searchroommate(roommaterank);
 	 	if (found==0)
 	 	{
 	 	 	printf("\nRoommate not found!!");
 	 	 	goto z;
 	 	}
 	 	if  (found==-1)
 	 	{
 	 	 	printf("No roommate available ");
 	 	 	allot=0;
            return allot;
 	 	}
 	 	for (i=0; i<10; i++)
 	 	{
 	 	 	if (Qblock_2bed[i][0]==0)
 	 	 	{
 	 	 	 	Qblock_2bed[i][0]=front;
                Qblock_2bed[i][1]=roommaterank;
 	 	 	 	printf("CONGRATULATIONS !! Student Rank %d and %d have been alloted 2 bed AC room in Q Block", present[front], roommaterank);
 	 	 	 	allot=1;
                break;
 	 	 	}
 	 	}
 	 	if (allot==0)
 	 	 	printf("Sorry, Q Block is full");
 	}
 	return allot;
}

int main()
{
    int n,opt,rollno,counter=0,b,slot,total,flag=0;
    float cgpa;
    char name[100];
    FILE *fptr;
    char str[MAXCHAR],details[15][100];
    printf("\t>>>   WELCOME TO VIT  <<<\n");
    // TOTAL NUMBER OF STUDENTS IS 12
    cse_branch = (struct hash *)calloc(4, sizeof(struct hash));
    ece_branch = (struct hash *)calloc(4, sizeof(struct hash));
    mech_branch = (struct hash *)calloc(4, sizeof(struct hash));
    struct node *b1list=NULL, *b2list=NULL, *b3list=NULL;
    while(counter<=12)
    {
        printf("\n1.Get Details from VIT Database\n2.Search\n3.Display Students\n4.Calculate NCGPA\n5.Exit\nEnter your choice : ");
        scanf("%d",&opt);
        switch(opt)
        {
        case 1:
            if(flag==1)
            {
                printf("Student Details Received.\n");
                break;
            }
            for (int i = 0; i <= 10000; i++)
            {
                printf("\rGETTING INFORMATION....PLEASE WAIT  %d", i/100);
            }
            printf("\n");
            // File handling is used, details of students stored as stored in a database
            fptr = fopen("StuDetails.txt","r+");
            while (fgets(str, MAXCHAR, fptr) != NULL)
            {
                int j=0,ctr=0;
                for(int i=0;i<=(strlen(str));i++)
                {
                    if(str[i]==' '||str[i]=='\0')
                    {
                        details[ctr][j]='\0';
                        ctr++;
                        j=0;
                    }
                    else
                    {
                        details[ctr][j]=str[i];
                        j++;
                    }
                }
                rollno=atoi(details[0]);
                strcpy(name,details[1]);
                cgpa=atof(details[2]);
                b=atoi(details[3]);
                slot=atoi(details[4]);
                if(b==1)
                    insert(cse_branch, rollno, name, cgpa, slot);
                else if(b==2)
                    insert(ece_branch, rollno, name, cgpa, slot);
                else if (b==3)
                    insert(mech_branch, rollno, name, cgpa, slot);
                counter++;
            }
            flag=1;
            break;
        case 2:
            system("cls");
            printf("\nEnter the Roll No to search:");
            scanf("%d", &rollno);
            b=search_details(cse_branch,rollno);
            if(b==0)
                b=search_details(ece_branch,rollno);
            if(b==0)
                b=search_details(mech_branch,rollno);
            if(b==0)
                printf("Student Not Found!\n");
            break;
        case 3:
            system("cls");
            printf("\tDISPLAYING ALL RECORDS ");
            printf("\n--------------------------------------------------------");
            printf("\n\tCSE BRANCH");
            display(cse_branch);
            printf("\n--------------------------------------------------------");
            printf("\n\tECE BRANCH");
            display(ece_branch);
            printf("\n--------------------------------------------------------");
            printf("\n\tMECHANICAL BRANCH");
            display(mech_branch);
            printf("\n--------------------------------------------------------");
            printf("\n\nPress any key to continue ");
            getch();
            system("cls");
            break;
        case 4:
            counter=3*n+1;
            break;
        case 5:
            exit(0);
        default:
            printf("Enter correct option!!!\n");
            break;
        }
    }
    system("cls");
    printf("\n\tDISPLAYING BRANCH TOPPER DETAILS\n");
    topper(cse_branch,"CSE");
    topper(ece_branch,"ECE");
    topper(mech_branch,"MECHANICAL");
    printf("\n\nPress any key to continue: ");
    getch();
    system("cls");
    b1list=ncgpalist(cse_branch);
    b2list=ncgpalist(ece_branch);
    b3list=ncgpalist(mech_branch);

    printf("\nNCGPA list of CSE students:\n");
    displaylist(b1list);
    printf("\nNCGPA list of ECE students:\n");
    displaylist(b2list);
    printf("\nNCGPA list of MECHANICAL students:\n");
    displaylist(b3list);
    mergeall(b1list,b2list,b3list);
    system("pause");
    system("cls");
    printf("NCGPA RANK LIST:\n");
    total=printlist();
    printf("\nPROCEED TO ROOM COUNSELLING DAY? IF YES PRESS 1, ELSE EXIT.\n");
    scanf("%d",&opt);
    if(opt!=1)
        exit(0);
    system("cls");
    printf(">>>>  WELCOME TO VIT HOSTEL ROOM COUNSELLING  <<<<\n");
    printf("\nProceed for registration:\n");
    registration(total);
    printf("\t\tROOMS AVAILABLE\n");
    printf("\tROOM TYPE\t\tTOTAL ROOMS\tCHOICE\n");
    printf("   Q BLOCK 1 BED AC\t\t\t10\t  1\n   Q BLOCK 2 BED AC\t\t\t10\t  2\n");
    int front=1;
    while (present[front]!=0)
    {
        int allot=0, choice;
        while (allot==0)
        {
            printf("\n\nStudent rank %d Choose your room type : ", present[front]);
            scanf("%d", &choice);
 	 	 	allot=chooseroom(choice, front);
            if (allot==1)
 	 	 	 	front++;
 	 	}
 	}

    printf("\n\n    COUNSELLING PROCESS OVER !!\n");
    printf("A provisional hostel room allotment letter will be available in VTOP under Hostels Menu. This allotment will be confirmed subject to payment of balance Hostel Fee and entire Tuition fees for the academic year 2020-21.\n");
    printf("\n----------------THE END----------------");
    return 0;
}