FCFS implmentation in C.

fcfs.c

#include <stdio.h> 
  
// Function to find the waiting time for all  
// processes 
void findWaitingTime (int processes [], int n, int bt [], int wt []) 
{ 
    // waiting time for first process is 0 
    wt [0] = 0; 
  
    // calculating waiting time 
    for (int i = 1; i < n; i++) 
        wt[i] = bt[i-1] + wt[i-1]; 
} 
  
// Function to calculate turn around time 
void findTurnAroundTime(int processes[], int n,  
                  int bt[], int wt[], int tat[]) 
{ 
    // calculating turnaround time by adding 
    // bt[i] + wt[i] 
    for (int  i = 0; i < n ; i++) 
        tat[i] = bt[i] + wt[i]; 
} 
  
//Function to calculate average time 
void findavgTime( int processes[], int n, int bt[]) 
{ 
    int wt[n], tat[n], total_wt = 0, total_tat = 0; 
  
    //Function to find waiting time of all processes 
    findWaitingTime(processes, n, bt, wt); 
  
    //Function to find turn around time for all processes 
    findTurnAroundTime(processes, n, bt, wt, tat); 
  
    // Calculate total waiting time and total turn  
    // around time 
    for (int  i=0; i<n; i++) 
    { 
        total_wt = total_wt + wt[i]; 
        total_tat = total_tat + tat[i]; 
        printf("Process id: %d \nBurst time: %d \nWaiting time: %d \nTurnaround time: %d\n",i+1,bt[i],wt[i],tat[i]);
    } 
    
    float avg_tt=total_tat/n;
    float avg_wt=total_wt/n;
  
    printf("The average turnaround time is: %f \n",avg_tt);
    printf("The average waiting time is: %f \n",avg_wt);
} 
  
// Driver code 
int main() 
{ 
    //process id's 
    int processes[] = { 1, 2, 3}; 
    int n = sizeof processes / sizeof processes[0]; 
  
    //Burst time of all processes 
    int  burst_time[] = {10, 5, 8}; 
  
    findavgTime(processes, n,  burst_time); 
    return 0; 
}