FCFS

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

struct gt
{
    int pro;
    int time;
};

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

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

    printf("Enter number of processes : ");
    cin>>n;
    int arrTemp[1000];
    int burTemp[1000];
    int process[1000];
    for(i=0; i<n; i++){
        printf("Enter burst time and arrival time of p%d : ", i);
        cin>>bur[i]>>arr[i];
        process[i]=i;
        arrTemp[i]=arr[i];
        burTemp[i]=bur[i];
    }

    for(i=0; i<n; i++){
        for(j=i+1; j<n; j++){
            if(arrTemp[i]>arrTemp[j]){
                swap(arrTemp[i], arrTemp[j]);
                swap(burTemp[i], burTemp[j]);
                swap(process[i], process[j]);
            }
        }
    }

    wt[process[0]]=0;

    printf("\n\t\t****Gantt Chart****\n");
    printf("%d__[p%d]__%d  ", arrTemp[0], process[0], arrTemp[0]+burTemp[0]);
    int presentTime=arrTemp[0]+burTemp[0];

    double sum=0.0;



    for(i=1; i<n; i++){
        int strt, endd;

        if(presentTime>arrTemp[i]){
            wt[i]=presentTime-arrTemp[i];
            strt=presentTime;
            endd=presentTime+burTemp[i];
            presentTime=endd;
        }
        else{
            wt[i]=0;
            strt=arrTemp[i];
            endd=arrTemp[i]+burTemp[i];
            presentTime=endd;
        }

        printf("%d__[p%d]__%d   ", strt, process[i], endd);
        sum+=(double)wt[i];
    }
    printf("\n\n");

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

    for(i=0; i<n; i++){
        printf("    p%d            %d\n", i, wt[i]);
    }
    printf("\n\nAverage of waiting time : %.2lf\n", sum/n);



}