Priority Scheduling

#include <bits/stdc++.h>
using namespace std;

struct gt
{
    int pro;
    int time;
};

int arr[1000], bur[1000], pr[1000], wt[1000], tmp[1000];
vector<gt>v;

int main()
{
    int n, i, j,k, x, y;

    int min1, min2, mx, st, flg;

    struct gt temp;

    cout<<"Enter number of processes : ";
    cin>>n;

    for(i=1; i<=n; i++)
    {
        printf("Enter burst time, arrival time and priority of process %d : ", i);
        scanf("%d%d%d", &bur[i], &arr[i], &pr[i]);
        tmp[i]=bur[i];
    }

    mx = 0;

    for(i=1; i<=n; i++)
    {
        if(arr[i]==0)
        {
            if(pr[i]>mx)
            {
                mx = pr[i];
                st=i;
            }
        }
    }

    memset(wt, 0, sizeof wt);

    temp.pro=st;
    temp.time=0;

    v.push_back(temp);

    int t=1;
    int now = st;
    tmp[now]--;

    while(1)
    {

        min1=t;
        mx = pr[now];
        for(i=1; i<=n; i++)
        {
            if(i!=now && arr[i]<min1 && tmp[i]>0 && arr[i]<=t && pr[i]>mx)
            {
                min1=arr[i];
                mx = pr[i];
                now=i;
            }
        }

        for(i=1; i<=n; i++)
        {
            if(i!=now && tmp[i]>0 && arr[i]<=t)
            {
                wt[i]++;
            }
        }

        temp.pro=now;
        temp.time=t;
        v.push_back(temp);

        tmp[now]--;
        t++;

        if(tmp[now]==0)
        {

            mx = 0;
            min1=t;
            flg=0;
            for(i=1; i<=n; i++)
            {
                if(arr[i]<=t && tmp[i]>0 && pr[i]>mx && arr[i]<=min1)
                {
                    flg=1;
                    min1 = arr[i];
                    mx = pr[i];
                    now=i;
                }
            }

            if(flg==0)
            {
                min1=99999999;
                mx=0;
                for(i=1; i<=n; i++)
                {
                    if(tmp[i]>0 && arr[i]<min1 && pr[i]>mx)
                    {
                        min1=arr[i];
                        mx=pr[i];
                        t=arr[i];
                        now=i;
                    }
                }

            }

        }

        int koyta=0;

        for(i=1; i<=n; i++)
        {
            if(tmp[i]==0)koyta++;
        }
        if(koyta==n)break;
    }


    printf("\n\t****Individual Waiting time****\n");
    printf("\t  Process            Waiting Time\n");

    for(i=1; i<=n; i++)
    {
        printf("\t      %d                 %d\n", i, wt[i]);
    }
    printf("\n");



    double sum = 0.0;

    for(i=1; i<=n; i++)
    {
        sum+=(double)wt[i];
    }
    printf("Average waiting time : %.3lf\n", sum/n);



    printf("\n\t\t*****Gantt Chart*****\n\n");

//    for(i=0; i<v.size(); i++)
//    {
//        printf("p%d ", v[i].pro);
//    }
//    printf("\n");
//
//    for(i=0; i<v.size(); i++)
//    {
//        if(v[i].time<=9)printf("%d  ", v[i].time);
//        else printf("%d ", v[i].time);
//    }
//    printf("\n");

int process, startTime, endTime;
    int cnt=0;
    for(i=0; i<v.size();){
            cnt++;
        process = v[i].pro;
        startTime = v[i].time;
        endTime;
        for(j=i+1; j<v.size(); j++){
            if(v[j].pro!=process){
                i=j;
                endTime=v[j-1].time+1;
                break;
            }
        }
        if(j>=(v.size()-1)){
            endTime=v[v.size()-1].time+1;
            i=v.size();
        }
        printf("%d __[p%d]__ %d  ", startTime, process, endTime);
    }


     printf("\n");

}

/*4
4 0 5
10 1 1
2 1 2
5 2 3*/