SJF(non-preemptive)

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

struct gt
{
    int pro;
    int time;
};

vector<gt>v;
int arr[1000], bur[1000], tmp[1000], wt[1000], flg;
int main()
{
    int n, i, j, k, x, y, min1, min2, st;
    struct gt temp;

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

    for(i=0; i<n; i++)
    {
        printf("Enter arrival and burst time of process %d : ", i);
        scanf("%d%d", &arr[i], &bur[i]);
        tmp[i]=bur[i];
    }

    min1=99999999;

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

        for(i=0; 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)
        {

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

            if(flg==0)
            {
                min1=99999999;
                min2=99999999;
                for(i=0; i<n; i++)
                {
                    if(tmp[i]>0 && arr[i]<=min1 && tmp[i]<min2)
                    {
                        min1=arr[i];
                        min2=tmp[i];
                        t=arr[i];
                        now=i;
                    }
                }

            }

        }

        int koyta=0;

        for(i=0; 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=0; i<n; i++)
    {
        printf("\t      %d                 %d\n", i, wt[i]);
    }
    printf("\n");



    double sum = 0.0;

    for(i=0; 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");

    return 0;
}