diff --git a/hello.cpp b/hello.cpp
index 4f6a268..3a87b4c 100644
--- a/hello.cpp
+++ b/hello.cpp
@@ -1,7 +1,191 @@
-#include<bits/stdc++.h>
+#include <iostream>
 using namespace std;
-inrt main(){
-cout<<"hello world x";
-return 0;
-}
 
+int main()
+{
+    int n,bt[20],wt[20],tat[20],avwt=0,avtat=0,i,j,p[20],pos,temp;
+    cout<<"Enter total number of processes:\n";
+    cin>>n;
+    cout<<"Enter a process: \n"<<"1. FCFS\n"<<"2. SJF\n"<<"3. Priority\n"<<"4. Round Robin\n";
+    int x;
+    cin>>x;
+    switch(x)
+    {
+        case 1:
+            cout<<"Enter Process Burst Time\n";
+            for(i=0;i<n;i++)
+            {
+                cout<<i+1<<": ";
+                cin>>bt[i];
+            }
+            wt[0]=0;
+            for(i=1;i<n;i++)
+            {
+                wt[i]=0;
+                for(j=0;j<i;j++)
+                    wt[i]+=bt[j];
+            }
+            cout<<"\nProcess\t\tBurst Time\tWaiting Time\tTurnaround Time\n";
+            for(i=0;i<n;i++)
+            {
+                tat[i]=bt[i]+wt[i];
+                avwt+=wt[i];
+                avtat+=tat[i];
+                cout<<i+1<<"\t\t"<<bt[i]<<"\t\t"<<wt[i]<<"\t\t"<<tat[i]<<"\n";
+            }
+            avwt/=n;
+            avtat/=n;
+            cout<<"\nAverage Waiting Time: " <<avwt<<"\n";
+            cout<<"Average Turnaround Time: " <<avtat;
+
+            break;
+        case 2:
+            cout<<"Enter Process Burst Time\n";
+            for(i=0;i<n;i++)
+            {
+                cout<<i+1<<": ";
+                cin>>bt[i];
+                p[i]=i+1;
+            }
+            for(i=0;i<n;i++)
+            {
+                pos=i;
+                for(j=i+1;j<n;j++)
+                {
+                    if(bt[j]<bt[pos])
+                        pos=j;
+                }
+                temp=bt[i];
+                bt[i]=bt[pos];
+                bt[pos]=temp;
+                temp=p[i];
+                p[i]=p[pos];
+                p[pos]=temp;
+            }
+            wt[0]=0;
+            for(i=1;i<n;i++)
+            {
+                wt[i]=0;
+                for(j=0;j<i;j++)
+                    wt[i]+=bt[j];
+            }
+            cout<<"\nProcess\t\tBurst Time\tWaiting Time\tTurnaround Time\n";
+            for(i=0;i<n;i++)
+            {
+                tat[i]=bt[i]+wt[i];
+                avwt+=wt[i];
+                avtat+=tat[i];
+                cout<<p[i]<<"\t\t"<<bt[i]<<"\t\t"<<wt[i]<<"\t\t"<<tat[i]<<"\n";
+            }
+            avwt/=n;
+            avtat/=n;
+            cout<<"\nAverage Waiting Time: " <<avwt<<"\n";
+            cout<<"Average Turnaround Time: " <<avtat;
+
+            break;
+        case 3:
+            int pr[20];
+            cout<<"Enter Process Burst Time and Priority\n";
+            for(i=0;i<n;i++)
+            {
+                cout<<i+1<<": ";
+                cin>>bt[i]>>pr[i];
+                p[i]=i+1;
+            }
+            for (i=0;i<n;i++)
+            {
+                pos=i;
+                for (j=i+ 1 ;j<n;j++)
+                {
+                    if (pr[j]<pr[pos])
+                        pos=j;
+                }
+                temp=pr[i];
+                pr[i]=pr[pos];
+                pr[pos]=temp;
+                temp=bt[i];
+                bt[i]=bt[pos];
+                bt[pos]=temp;
+                temp=p[i];
+                p[i]=p[pos];
+                p[pos]=temp;
+            }
+            wt[0]=0;
+            for(i=1;i<n;i++)
+            {
+                wt[i]=0;
+                for(j=0;j<i;j++)
+                    wt[i]+=bt[j];
+            }
+            cout<<"\nProcess\t\tBurst Time\tWaiting Time\tTurnaround Time\n";
+            for(i=0;i<n;i++)
+            {
+                tat[i]=bt[i]+wt[i];
+                avwt+=wt[i];
+                avtat+=tat[i];
+                cout<<p[i]<<"\t\t"<<bt[i]<<"\t\t"<<wt[i]<<"\t\t"<<tat[i]<<"\n";
+            }
+            avwt/=n;
+            avtat/=n;
+            cout<<"\nAverage Waiting Time: " <<avwt<<"\n";
+            cout<<"Average Turnaround Time: " <<avtat;
+            break;
+        case 4:
+            int count,j,time,remain,flag=0,quantum, min= 0,start=0;
+            int wait_time=0,turnaround_time=0,at[10],bt[10],rt[10];
+            remain=n;
+            count=0;
+            while(count<n)
+            {
+                cout<<"Enter Arrival Time and Burst Time for Process " <<count+1<<": ";
+                cin>>at[count];
+                cin>>bt[count];
+                rt[count]=bt[count];
+                count++;
+            }
+            cout<<"Enter Time Quantum: ";
+            cin>>quantum;
+            cout<<"\nProcess\t\tBurst Time\tWaiting Time\tTurnaround Time\n";
+            min=at[0];
+            for(i=1;i<n;i++)
+            {
+                if (at[i]<=min)
+                {
+                    min=at[i];
+                    start=i;
+                }
+            }
+            for(time=min,count=start;remain!=0;)
+            {
+                if(rt[count]<=quantum && rt[count]> 0 )
+                {
+                    time+=rt[count];
+                    rt[count]= 0;
+                    flag=1;
+                }
+                else if(rt[count]>0)
+                {
+                    rt[count]-=quantum;
+                    time+=quantum;
+                }
+                if(rt[count]==0&&flag==1)
+                {
+                    remain--;
+                    cout<<count+ 1<<"\t\t"<<bt[count]<<"\t\t"<< time-at[count]-bt[count]<<"\t\t"<< time-at[count]<<"\n";
+                    wait_time+=time-at[count]-bt[count];
+                    turnaround_time+=time-at[count];
+                    flag= 0 ;
+                }
+                if (count==n-1)
+                    count= 0;
+                else if(at[count+1]<=time)
+                    count++;
+                else
+                    count= 0;
+            }
+            cout<<"\nAverage Waiting Time= " <<wait_time/n;
+            cout<< "\nAvg Turnaround Time = " <<turnaround_time/n;
+            break;
+    }
+    return 0;
+}