priority.cpp

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

struct Process { 
	int pid;
	int bt; 
	int priority;
}; 

bool comparison(Process a, Process b) { 
	return (a.priority > b.priority); 
} 

void findWaitingTime(Process proc[], int n, int wt[]) { 
	wt[0] = 0; 
	for (int i = 1; i < n ; i++ ) 
		wt[i] = proc[i-1].bt + wt[i-1] ; 
} 

void findTurnAroundTime( Process proc[], int n, int wt[], int tat[]) { 
	for (int i = 0; i < n ; i++) 
		tat[i] = proc[i].bt + wt[i]; 
} 

void findavgTime(Process proc[], int n) { 
	int wt[n], tat[n], total_wt = 0, total_tat = 0; 
	findWaitingTime(proc, n, wt); 
	findTurnAroundTime(proc, n, wt, tat); 
	cout << "\nProcesses "<< " Burst time "<< " Waiting time " << " Turn around time\n"; 
	for (int i=0; i<n; i++) { 
		total_wt = total_wt + wt[i]; 
		total_tat = total_tat + tat[i]; 
		cout << " " << proc[i].pid << "\t\t"<< proc[i].bt << "\t " << wt[i] << "\t\t " << tat[i] <<endl; 
	} 
	cout << "\nAverage waiting time = "<< (float)total_wt / (float)n; 
	cout << "\nAverage turn around time = "<< (float)total_tat / (float)n; 
} 

void priorityScheduling(Process proc[], int n) { 
	sort(proc, proc + n, comparison); 
	cout<< "Order in which processes gets executed \n"; 
	for (int i = 0 ; i < n; i++) 
		cout << proc[i].pid <<" " ; 
	findavgTime(proc, n); 
} 

int main() { 
	Process proc[] = {{0, 3, 1}, {1, 6, 0}, {2, 4, 2}, {3,7,3},{4,3,1}}; 
	int n = sizeof proc / sizeof proc[0]; 
	priorityScheduling(proc, n); 
	return 0; 
}