preemptive sjf added

Author: 27-Abhi

.gitignore

@@ -1,3 +1,4 @@
 /sstf/target/
 /fcfs/target/
 /NonprempriveSJF/target/
+/PreemptiveSJF/target/

PreemptiveSJF/pom.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.mycompany</groupId>
+    <artifactId>PreemptiveSJF</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven.compiler.source>16</maven.compiler.source>
+        <maven.compiler.target>16</maven.compiler.target>
+        <exec.mainClass>com.mycompany.preemptivesjf.PreemptiveSJF</exec.mainClass>
+    </properties>
+</project>

PreemptiveSJF/src/main/java/com/mycompany/preemptivesjf/PreemptiveSJF.java

@@ -0,0 +1,94 @@
+/*
+ * Click nbfs://nbhost/SystemFileSystem/Templates/Licenses/license-default.txt to change this license
+ */
+
+package com.mycompany.preemptivesjf;
+import java.util.*;
+/**
+ *
+ * @author lenovo
+ */
+public class PreemptiveSJF {
+
+    public static void main(String[] args) {
+        System.out.println("Enter the number of processes");
+        Scanner sc= new Scanner(System.in);
+       int pno=sc.nextInt();
+       
+       int[] at=new int[pno];
+       int[] bt=new int[pno];
+       int[] rt=new int[pno]; //remaining time
+       int[] wt=new int[pno];
+        int[] bt1=new int[pno];
+       int[] ct=new int[pno];
+       int[] flag=new int[pno];
+       int[] tat=new int[pno];
+       int[] pid=new int[pno];
+       
+       System.out.println("Enter the arrival time");
+       for(int i=0;i<pno;i++)
+       {
+           at[i]=sc.nextInt();
+       }
+       
+       System.out.println("Enter the burst time");
+       for(int i=0;i<pno;i++)
+       {
+           bt[i]=sc.nextInt();
+       }
+        System.out.println("Please wait!");
+       //initialising flag
+        for(int i=0;i<pno;i++)
+       {
+          flag[i]=0;
+       }
+        
+        //copying burst time in remaining time
+       
+       for(int i=0;i<pno;i++)
+       {
+          rt[i]=bt[i];
+          bt1[i]=bt[i]; //for priniting purpose only
+         
+       }
+       int st=0;
+       int count=0;
+       int smallest=0;
+      //max number
+       int end;//end time
+       for(st=0;count!=pno;st++)
+       {
+            int min=99999;
+           
+        for(int i=0; i<pno; i++)
+        {
+            if(at[i]<=st && bt[i]<min && bt[i]>0 ) //chosing the smallest burst time
+                smallest=i; //choosing the smallest burst time of all
+                min=bt[i]; 
+        }
+        bt[smallest]--; //dec burst time by 1...we decrement step by step i.e 1 by 1 to check if there is any other process at that particular time having burst time less
+       
+
+        if(bt[smallest]==0) // iterate through loop untill bt=0 i.e process execution is completed
+        {
+            pid[smallest]++;
+            count++;
+            end=st+1;
+            tat[smallest] = end - at[smallest];
+            ct[smallest] = end;
+            wt[smallest] =tat[smallest] - bt1[smallest];
+            
+        }
+       
+       }
+        System.out.println("\tpid\t\tat\t\tbt\t\ttat\t\twt\t\tct\t\t");
+      for(int i=0;i<pno;i++)
+      {
+      System.out.println("\t\t"+pid[i]+"\t\t"+at[i]+"\t\t"+bt1[i]+"\t\t"+tat[i]+"\t\t"+wt[i]+"\t\t"+ct[i]+"\t\t");
+      }
+     
+       
+       
+        
+    }
+}