Disk.c

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int q[10], noq, cp, i, j, temp;
void fcfs();
void scan();
void cscan();
void main()
{
    int n,  x;
    //printf("Enter the maximum number of cylinders : ");
    //scanf("%d", &n);
    printf("Enter the number of queues : ");
    scanf("%d", &noq);
    printf("Enter the position of queues :-\n");
    for(i=0;i<noq;i++)
    {
        scanf("%d", &q[i]);
    }
    printf("Enter the current position of the head : ");
    scanf("%d", &cp);
    do
    {
        printf("Choose disc scheduling type :-\n");
        printf("1. FCFS\n");
        //printf("2. SSTF\n");
        printf("2. SCAN\n");
        printf("3. CSCAN\n");
        printf("4. Exit\n");
        scanf("%d", &x);
        switch(x)
        {
            case 1 : fcfs();
                 break;
            //case 2 : sstf();
            //   break;
            case 2 : scan();
                 break;
            case 3 : cscan();
                 break;
            /*case 4 : look();
                 break;
            case 5 : clook();
                 break;*/
            case 4 : exit(0);
            default : printf("Enter a valid option : ");
                  break;
        }
    }while(1);
}
void fcfs()
{
    int i, t=0, cpp;
    cpp=cp;
    //printf("%d-->",cp);
    for(i=0;i<noq;i++)
    {
        t += abs(cpp-q[i]);
        printf("%d-->",cpp);
        cpp = q[i];
    }
    printf("%d\n",cpp);
    printf("Seek time : %d\n", t);
}
/*void sstf()
{
    int min=999, temp
    for(i=0;i<noq;i++)
    {
        if(visit[i]==0)
        {
            if(min>abs(st-q[i])
            {
                min = abs(st-q[i]);
                p = i;
            }
        }
    /*for(i=0;i<noq;i++)
    {
        for(j=i+1;j<noq;j++)
        {
            if(q[i]>q[j])
            {
                temp=q[i];
                q[i] = q[j];
                q[j] = temp;
            }
        }
    }
}*/
void scan()
{
    //printf("test\n");
    int st, e, t=0, max, dloc;
    /*for(i=0;i<noq;i++)
    {
        if(q[i]>q[i+1])
        {
            temp=q[i];
            q[i] = q[i+1];
            q[i+1] = temp;
        }
    }*/
    //printf("test\n");
    printf("Enter the disc movement range -\n");
    printf("Starting : ");
    scanf("%d",&st);
    printf("To : ");
    scanf("%d",&e);
    for(i=0;i<noq;i++);
    q[noq]=cp;
    noq+=1;
    for(i=0;i<noq;i++)
    {
        for(j=i;j<noq;j++)
        {
            if(q[i]>q[j])
            {
                temp=q[i];
                q[i] = q[j];
                q[j] = temp;
            }
        }
    }
    max = q[noq-1];
    //printf("test\n");
    for(i=0;i<noq;i++)   // to find loc of disc in array
    {
        if(cp==q[i])
        {
            dloc=i;
            break;
        }
    }
    //printf("test\n");
    for(i=dloc;i>=0;i--)
    {
        //printf("test1\n");
        printf("%d-->",q[i]);
    }
    //printf("test\n");
    //if(q[i]!=st)
        printf("0-->");
    //printf("test\n");
    for(i=dloc+1;i<noq-1;i++)
    {
        printf("%d-->",q[i]);
    }
    //printf("test\n");
    printf("%d\n",q[i]);
    t=q[dloc]+max;
        printf("\nSeek time = %d\n",t);
    /*do
    {
        printf("%d-->",cp);
        for(i=cp;i!=e;i++)
        {
            for(j=0;j<noq;j++)
            {
                if(i==q[j])
                {
                    if(v[j]==0)
                    {
                        printf("%d-->",i);
                        v[j]==1;
                        t+=abs(cp-i);
                        cp=i;
                    }
                }
            }
        }
        if(e!=cp)
            printf("%d-->",e);
        t+=abs(cp-e);
        cp=e;
        for(i=0;i<noq;i++)
            if(v[i]!=1)
                f=0;
        if(f==0)
        {
            for(i=e;i!=st;i--)
            {
                for(j=0;j<noq;j++)
                {
                    if(i==q[j])
                    {
                        if(v[j]==0)
                        {
                            printf("%d-->",i);
                            v[j]==1;
                            t+=abs(cp-i);
                            cp=i;
                        }
                    }
                }
            }
            t+=abs(cp-i);
            if(st!=cp)
                printf("%d",st);
            t+=abs(cp-st);
            printf("\n");
        }
        printf("Seek time : %d\n", t);
        break;
    }while(1);*/
    //printf("%d\n",t);*/
}
void cscan()
{
    int st, e, t=0, f=1, max, dloc;
    int c1=0,c2=0,q1[10],q2[10];
    printf("Enter the disc movement range -\n");
    printf("Starting : ");
    scanf("%d",&st);
    printf("To : ");
    scanf("%d",&e);
    for(i=0;i<noq;i++)
    {
        for(j=i;j<noq;j++)
        {
            if(q[i]>q[j])
            {
                temp=q[i];
                q[i] = q[j];
                q[j] = temp;
            }
        }
    }
    for(i=0;i<noq;i++)
    {
        if(q[i]>=cp)
        {
            q1[c1++] = q[i];
        }
        else
        {
            q2[c2++] = q[i];
        }
    }
    if(cp!=q1[0])
        printf("%d-->",cp);
    for(i=0;i<c1;i++)
    {
        printf("%d-->",q1[i]);
    }
    if(e!=cp)
        printf("%d-->",e);
    t += (e-cp);
    if(st!=q2[0])
        printf("%d-->",st);
    for(i=0;i<c2-1;i++)
    {
        printf("%d-->",q2[i]);
    }
    t += (e-st)+q2[i];
    printf("%d\n",q2[i]);
    printf("Seek time : %d\n", t);
    /*for(i=0;i<noq;i++)
    {
        for(j=i;j<noq;j++)
        {
            if(q[i]>q[j])
            {
                temp=q[i];
                q[i] = q[j];
                q[j] = temp;
            }
        }
    }
    max = q[noq];
    for(i=0;i<noq;i++)
    {
        if(cp==q[i])
        {
            dloc=i;
            break;
        }
    }
    for(i=dloc;i<noq;i++)
    {
        printf("%d-->",q[i]);
    }
    if(q[i]!=e)
        printf("%d-->",e);
    printf("%d-->",st);
    for(i=0;i<dloc;i++)
    {
        printf("%d-->",q[i]);
    }
    printf("%d\n",q[i]);
    t=cp+max;
        printf("\nSeek time = %d\n",t);*/
}