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docs: update the whole repository

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* fix some bugs
* delete duplicate files
* format code
This commit is contained in:
yanglbme
2019-05-09 19:32:54 +08:00
parent 163db8521a
commit 29948363da
368 changed files with 4372 additions and 30841 deletions
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50
Others/SJF.java
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@ -1,14 +1,16 @@
package Others;
/**
* <h2>Shortest job first.</h2>
* <p>Shortest job first (SJF) or shortest job next, is a scheduling policy
* that selects the waiting process with the smallest execution time to execute next
* Shortest Job first has the advantage of having minimum average waiting time among all scheduling algorithms.
* It is a Greedy Algorithm.
* It may cause starvation if shorter processes keep coming.
* This problem has been solved using the concept of aging.</p>
* @author shivg7706
* @since 2018/10/27
*/
* <h2>Shortest job first.</h2>
* <p>Shortest job first (SJF) or shortest job next, is a scheduling policy
* that selects the waiting process with the smallest execution time to execute next
* Shortest Job first has the advantage of having minimum average waiting time among all scheduling algorithms.
* It is a Greedy Algorithm.
* It may cause starvation if shorter processes keep coming.
* This problem has been solved using the concept of aging.</p>
*
* @author shivg7706
* @since 2018/10/27
*/
import java.util.Scanner;
import java.util.ArrayList;
@ -71,17 +73,17 @@ class Schedule {
void startScheduling() {
processes.sort(new Comparator<Process>() {
@Override
public int compare (Process a, Process b) {
public int compare(Process a, Process b) {
return a.arrivalTime - b.arrivalTime;
}
});
while(!(arrivals.size() == 0 && remainingProcess.size() == 0)) {
while (!(arrivals.size() == 0 && remainingProcess.size() == 0)) {
removeFinishedProcess();
if(arrivals.get(timer) != null) {
if (arrivals.get(timer) != null) {
remainingProcess.addAll(arrivals.get(timer));
arrivals.remove(timer);
}
@ -91,12 +93,12 @@ class Schedule {
private int beta = 1;
@Override
public int compare (Process a, Process b) {
public int compare(Process a, Process b) {
int aRem = a.remainingTime;
int bRem = b.remainingTime;
int aprior = a.priority;
int bprior = b.priority;
return (alpha*aRem + beta*aprior) - (alpha*bRem + beta*bprior);
return (alpha * aRem + beta * aprior) - (alpha * bRem + beta * bprior);
}
});
@ -105,13 +107,13 @@ class Schedule {
timer++;
}
System.out.println("Total time required: " + (timer-1));
System.out.println("Total time required: " + (timer - 1));
}
void removeFinishedProcess() {
ArrayList<Integer> completed = new ArrayList<Integer>();
for (int i = 0; i < remainingProcess.size(); i++) {
if(remainingProcess.get(i).remainingTime == 0) {
if (remainingProcess.get(i).remainingTime == 0) {
completed.add(i);
}
}
@ -126,7 +128,7 @@ class Schedule {
}
public int timeElapsed(int i) {
if(!remainingProcess.isEmpty()) {
if (!remainingProcess.isEmpty()) {
gantChart.add(i, remainingProcess.get(0).pid);
remainingProcess.get(0).remainingTime--;
return 1;
@ -140,7 +142,7 @@ class Schedule {
if (remainingProcess.get(i).waitTime % 7 == 0) {
remainingProcess.get(i).priority--;
}
}
}
}
@ -163,11 +165,11 @@ class Schedule {
System.out.println("Process no.: " + i + " Wait time: " + processes.get(i).waitTime + " Turn Around Time: " + processes.get(i).turnAroundTime);
}
System.out.println("Average Waiting Time: " + waitTimeTot/noOfProcess);
System.out.println("Average TAT Time: " + tatTime/noOfProcess);
System.out.println("Throughput: " + (float)noOfProcess/(timer - 1));
System.out.println("Average Waiting Time: " + waitTimeTot / noOfProcess);
System.out.println("Average TAT Time: " + tatTime / noOfProcess);
System.out.println("Throughput: " + (float) noOfProcess / (timer - 1));
}
}
public class SJF {