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SystemsProgrammingAndOperat.../Codes/Group B/Assignment - 5/Priority (Non-Preemptive).cpp

101 lines
3.4 KiB
C++

#include<iostream>
#include<limits.h> // for INT_MAX
using namespace std;
struct sjf {
int burst, arrival, id, completion, waiting, turnaround, response, priority;
bool active;
};
sjf meh[30];
class lesgo {
public:
int n;
void priorityIn() {
cout << "\nEnter number of processes: ";
cin >> n;
for (int i = 1; i <= n; i++) {
cout << "\nEnter arrival time of P" << i << ": ";
cin >> meh[i].arrival;
cout << "\nEnter burst time of P" << i << ": ";
cin >> meh[i].burst;
cout << "\nEnter priority of P" << i << ": ";
cin >> meh[i].priority;
meh[i].id = i;
meh[i].active = false;
}
cout << "\n | Arrival | Burst | Priority\n";
for (int j = 1; j <= n; j++) {
cout << "P" << j << " | " << meh[j].arrival << " | " << meh[j].burst << " | " << meh[j].priority << "\n";
}
}
void priorityProcess() {
int k = 0; // Current time
int completed = 0; // Number of completed processes
while (completed < n) {
int highestPriority = INT_MAX;
int selectedProcess = -1;
// Find the process with the highest priority (smallest priority number) that has arrived and is not completed
for (int i = 1; i <= n; i++) {
if (meh[i].arrival <= k && !meh[i].active && meh[i].priority < highestPriority) {
highestPriority = meh[i].priority;
selectedProcess = i;
}
}
if (selectedProcess != -1) {
// Mark the process as active
meh[selectedProcess].active = true;
// If the process is starting now, calculate response time
if (meh[selectedProcess].response == 0) {
meh[selectedProcess].response = k - meh[selectedProcess].arrival;
}
// Execute the process
k += meh[selectedProcess].burst;
meh[selectedProcess].completion = k;
meh[selectedProcess].turnaround = meh[selectedProcess].completion - meh[selectedProcess].arrival;
meh[selectedProcess].waiting = meh[selectedProcess].turnaround - meh[selectedProcess].burst;
completed++;
} else {
// If no process is ready to run, just increment time
k++;
}
}
}
void displayMetrics() {
double totalWaiting = 0, totalTurnaround = 0, totalCompletion = 0;
cout << "\n\n | Completion time | Waiting time | Turnaround time | Response time\n";
for (int j = 1; j <= n; j++) {
totalWaiting += meh[j].waiting;
totalTurnaround += meh[j].turnaround;
totalCompletion += meh[j].completion;
cout << "P" << j << " | " << meh[j].completion
<< " | " << meh[j].waiting
<< " | " << meh[j].turnaround
<< " | " << meh[j].response << "\n";
}
cout << "\nAverage completion time: " << totalCompletion / n;
cout << "\nAverage waiting time: " << totalWaiting / n;
cout << "\nAverage turnaround time: " << totalTurnaround / n;
}
};
int main() {
lesgo obj;
obj.priorityIn();
obj.priorityProcess();
obj.displayMetrics();
return 0;
}