Assignment : 3

 Assignment : 3

Set A:

i) Write the program to simulate FCFS CPU-scheduling. The arrival time and first CPU-

Burst for different n number of processes should be input to the algorithm. Assume that

the fixed IO waiting time (2 units). The next CPU-burst should be generated randomly.

The output should give Gantt chart, turnaround time and waiting time for each process.

Also find the average waiting time and turnaround time.

CODE:

👇

1. #include<stdio.h>
2. #include<stdlib.h>
3. struct proc_info
4. {
5. int atime;
6. int cpub;
7. int pid;  
8. } proc[20], temp;
9. 
   
10. struct ganttchart
11. {
12. int stime;
13. int pid;
14. int etime;
15. } gchart[20];
16. 
    
17. int i,j,ctime,n,gi=0,wtime[20],ttime[20];
18. 
    
19. void getprocs();
20. void start();
21. void dispgchart();
22. void addgchart(int);
23. void disptimes();
24. 
    
25. int main()
26. {
27. getprocs();
28. ctime=0;
29. start();
30. dispgchart();
31. disptimes();
32. }
33. 
    
34. void getprocs()
35. {
36. printf("\nHow many processes:");
37. scanf("%d",&n);
38. printf("\nPID\tATIME\tCPUB\n");
39. for(i=1; i<=n; i++)
40. {
41. scanf("%d%d%d",&proc[i].pid, &proc[i].atime, &proc[i].cpub);
42. }
43. for(i=1; i<=n; i++)
44. {
45. for(j=i+1; j<=n; j++)
46. {
47. if(proc[i].atime > proc[j].atime)
48. {
49. temp = proc[i];
50. proc[i] = proc[j];
51. proc[j] = temp;
52. }
53. }
54. }
55. for(i=1; i<=n; i++)
56. {
57. printf("\n%d\t%d\t%d",proc[i].pid, proc[i].atime, proc[i].cpub);
58. }
59. }//getprocs
60. 
    
61. 
    
62. void start()
63. {
64. int pid;
65. for(i=1; i<=n; i++)
66. {
67. wtime[i] = ctime-proc[i].atime;
68. addgchart(proc[i].pid);
69. while(proc[i].cpub != 0)
70. {
71. ctime++; 
72. proc[i].cpub--;
73. if(proc[i].cpub==0)//proc finished
74. {
75. printf("\nProc %d completed at time %d", proc[i].pid,ctime);
76. ttime[i] = ctime-proc[i].atime;
77. }//if
78. }
79. }
80. gchart[gi].etime = ctime;
81. }//start
82. 
    
83. void addgchart(int pid)
84. {
85. gchart[++gi].pid = pid;
86. gchart[gi].stime = ctime;
87. gchart[gi-i].etime = gchart[gi].stime;
88. }
89. 
    
90. 
    
91. void dispgchart()
92. {
93. printf("\n");
94. for(i=1; i<=n; i++)
95. printf("|--");
96. printf("|\n");
98. for(i=1; i<=n; i++)
99. printf("| %d", gchart[i].pid);
100. printf("|\n");
101. 
     
102. for(i=1; i<=gi; i++)
103. printf("|--");
104. printf("|\n");
105. 
     
106. for(i=1; i<=gi; i++)
107. printf("%d  ",gchart[i].stime);
108. 
     
109. printf("%d\t",gchart[gi].etime);
110. }
111. 
     
112. void disptimes()
113. {
114. int sumwt=0, sumtt=0,pid;
115. printf("\n\n**Waiting Time**");
116. printf("\nPID\tWtimes");
117. for(i=1; i<=n; i++)
118. {
119. printf("\n%d\t%d",proc[i].pid, wtime[i]);
120. sumwt += wtime[i];
121. }
122. printf("\nAverage: %.2f", (float)sumwt/n);
123. printf("\n\n**Turnaround Time**");
124. printf("\nPID\tttime");
125. for(i=1; i<=n;i++)
126. {
127. printf("\n%d\t%d",i,ttime[i]);
128. sumtt+=ttime[i];
129. }
130. printf("\nAverage: %.2f", (float)sumtt/n);
131. printf("\n");
132. }

ii) Write the program to simulate Non-preemptive Shortest Job First (SJF) -scheduling. The

arrival time and first CPU-burst for different n number of processes should be input to the

algorithm. Assume the fixed IO waiting time (2 units). The next CPU-burst should be

generated randomly. The output should give Gantt chart, turnaround time and waiting

time for each process. Also find the average waiting time and turnaround time.

CODE:

👇

1. #include<stdio.h>
2. #include<stdlib.h>
3. struct proc_info
4. {
5. int atime;
6. int cpub;
7. int pid; 
8. } proc[20], temp;
9. 
   
10. struct ganttchart
11. {
12. int stime;
13. int pid;
14. int etime;
15. } gchart[20];
16. 
    
17. int i,j,ctime,n,gi=0,wtime[20],ttime[20];
18. 
    
19. void getprocs();
20. void start();
21. void dispgchart();
22. void addgchart(int);
23. void disptimes();
24. 
    
25. int main()
26. {
27. getprocs();
28. ctime=0;
29. start();
30. dispgchart();
31. disptimes();
32. }
33. 
    
34. void getprocs()
35. {
36. printf("\nHow many processes:");
37. scanf("%d",&n);
38. printf("\nPID\tATIME\tCPUB\n");
39. for(i=1; i<=n; i++)
40. {
41. scanf("%d%d%d",&proc[i].pid, &proc[i].atime, &proc[i].cpub);
42. }
43. for(i=1; i<=n; i++)
44. {
45. for(j=i+1; j<=n; j++)
46. {
47. if(proc[i].cpub > proc[j].cpub)
48. {
49. temp = proc[i];
50. proc[i] = proc[j];
51. proc[j] = temp;
52. }
53. }
54. }
55. for(i=1; i<=n; i++)
56. {
57. printf("\n%d\t%d\t%d",proc[i].pid, proc[i].atime, proc[i].cpub);
58. }
59. }//getprocs
60. 
    
61. 
    
62. void start()
63. {
64. int pid;
65. for(i=1; i<=n; i++)
66. {
67. wtime[i] = ctime-proc[i].atime;
68. addgchart(proc[i].pid);
69. while(proc[i].cpub != 0)
70. {
71. ctime++; 
72. proc[i].cpub--;
73. if(proc[i].cpub==0)//proc finished
74. {
75. printf("\nProc %d completed at time %d", proc[i].pid,ctime);
76. ttime[i] = ctime-proc[i].atime;
77. }//if
78. }
79. }
80. gchart[gi].etime = ctime;
81. }//start
82. 
    
83. void addgchart(int pid)
84. {
85. gchart[++gi].pid = pid;
86. gchart[gi].stime = ctime;
87. gchart[gi-i].etime = gchart[gi].stime;
88. }
89. 
    
90. 
    
91. void dispgchart()
92. {
93. printf("\n");
94. for(i=1; i<=n; i++)
95. printf("|--");
96. printf("|\n");
98. for(i=1; i<=n; i++)
99. printf("| %d", gchart[i].pid);
100. printf("|\n");
101. 
     
102. for(i=1; i<=gi; i++)
103. printf("|--");
104. printf("|\n");
105. 
     
106. for(i=1; i<=gi; i++)
107. printf("%d  ",gchart[i].stime);
108. 
     
109. printf("%d\t",gchart[gi].etime);
110. }
111. 
     
112. void disptimes()
113. {
114. int sumwt=0, sumtt=0,pid;
115. printf("\n\n**Waiting Time**");
116. printf("\nPID\tWtimes");
117. for(i=1; i<=n; i++)
118. {
119. printf("\n%d\t%d",proc[i].pid, wtime[i]);
120. sumwt += wtime[i];
121. }
122. printf("\nAverage: %.2f", (float)sumwt/n);
123. printf("\n\n**Turnaround Time**");
124. printf("\nPID\tttime");
125. for(i=1; i<=n;i++)
126. {
127. printf("\n%d\t%d",i,ttime[i]);
128. sumtt+=ttime[i];
129. }
130. printf("\nAverage: %.2f", (float)sumtt/n);
131. printf("\n");
132. }

Set B:

ii) Write the program to simulate Non-preemptive Priority scheduling. The arrival time and

first CPU-burst and priority for different n number of processes should be input to the

algorithm. Assume the fixed IO waiting time (2 units). The next CPU-burst should be

generated randomly. The output should give Gantt chart, turnaround time and waiting

time for each process. Also find the average waiting time and turnaround time.

CODE:

👇

1. #include<stdio.h>
2. #include<stdlib.h>
3. 
   
4. struct proc_info
5. {
6. int atime;
7. int cpub;
8. int pid;
9. int priority;
10. } proc[20],temp;
11. 
    
12. struct ganttchart
13. {
14. int stime;
15. int pid;
16. int etime;
17. }gchart[20];
18. 
    
19. int i,j,n,ctime,gi=0,wtime[20],ttime[20];
20. 
    
21. void getprocs();
22. void start();
23. void dispgchart();
24. void addgchart(int);
25. void disptimes();
26. int finished();
27. 
    
28. int main()
29. {
30. // randomize();
31. getprocs();
32. ctime=0; //set current time to 0
33. start();
34. dispgchart();
35. disptimes();
36. }
37. 
    
38. void getprocs()
39. {
40. printf("\n How  many processes :"); 
41. scanf("%d",&n);
42. printf("\n PID\tATIME \tCPUB \tPRIORITY\n");
43. for(i=1;i<=n; i++)
44. {
45. scanf("%d%d%d%d",&proc[i].pid,&proc[i].atime,&proc[i].cpub,&proc[i].priority);
46. }
47. for(i=1;i<=n;i++)
48. {
49. for(j=i+1;j<=n;j++)
50. {
51. if(proc[i].priority<proc[j].priority)
52. {
53. temp=proc[i];
54. proc[i]=proc[j];
55. proc[j]=temp;
56. }
57. }
58. }
59. for(i=1;i<=n;i++)
60. {
61. //printf("%d\t",i);
62. printf("\n %d\t%d\t%d\t%d",proc[i].pid,proc[i].atime,proc[i].cpub,proc[i].priority);
63. }
64. }//get proc
65. 
    
66. void start()
67. {
68. int pid;
70. while(!finished())
71.       {
72. for(i=1;i<=n;i++)
73. {
74.    if(proc[i].atime<=ctime&&proc[i].cpub!=0)
75.              {
76. wtime[i]=ctime-proc[i].atime;
77. addgchart(proc[i].pid);
78. while(proc[i].cpub!=0)
79. {
80. ctime++; //increament current time
81. proc[i].cpub--;
82. if(proc[i].cpub==0) //proc finished
83. {
84. printf("\n Proc %d completed at time %d..",proc[i].pid,ctime);
85. ttime[i]=ctime-proc[i].atime;
86. break;
87. }
88. }
89. }
90. }
91.  }
92. gchart[gi].etime=ctime;
93. }//start
94. 
    
95. void addgchart(int pid)
96. {
97. gchart[++gi].pid=pid;
98. gchart[gi].stime=ctime;
99. gchart[gi-1].etime=gchart[gi].stime;
100. }
101. 
     
102. 
     
103. int finished()
104.  {
105.    for(i=1;i<=n; i++)
106.      {
107.        if(proc[i].cpub!=0)
108.         return 0;
109.      }
110.   return 1;
111. }
112. 
     
113. 
     
114. void dispgchart()
115. {
116.  printf("\n");
117.   for(i=1; i<=gi; i++)
118.     printf("|-----");
119.     printf("|\n");
120.     
121.     for(i=1;i<=gi;i++)
122.     printf("| %d ",gchart[i].pid);
123.     printf("|\n");
124.     
125.     for(i=1; i<=gi; i++)
126.     printf("|-----");
127.     printf("|\n");
128.     
129.     for(i=1;i<=gi;i++)
130.     printf("| %d ",gchart[i].stime);   
131.     
132.     printf("%d\n",gchart[gi].etime);
133. }
134. 
     
135.  void disptimes()
136.  {
137.  int sumwt=0, sumtt=0,pid;
138.  printf("\n***Waiting time***");
139.  printf("\nPID\tWtime");
140.  for(i=1; i<=n; i++)
141.   {
142.     printf("\n%d\t%d",proc[i].pid,wtime[i]);
143.     sumwt+=wtime[i];
144.   }
145.  printf("\nAverage:%.2f",(float)sumwt/n);
146.  printf("\n***Turnaround Time***");
147.  printf("\nPID\t ttime");
148.  for(i=1; i<=n; i++)
149.   {
150.      printf("\n%d\t%d",i,ttime[i]);
151.      sumtt+=ttime[i];
152.    }
153.  printf("\nAverage:%.2f",(float)sumtt/n);
154.  
155. }     

Set C

ii. Write the program to simulate Round Robin (RR) scheduling. The arrival time and first

CPU-burst for different n number of processes should be input to the algorithm. Also

give the time quantum as input. Assume the fixed IO waiting time (2 units). The next

CPU-burst should be generated randomly. The output should give Gantt chart, turnaround

time and waiting time for each process. Also find the average waiting time and

turnaround time.

CODE:

👇

1. #include<stdio.h>
2. #include<stdlib.h>
3. struct proc_info
4. {
5. int atime;
6. int cpub;
7. int pid; 
8. } proc[20], temp;
9. 
   
10. struct ganttchart
11. {
12. int stime;
13. int pid;
14. int etime;
15. } gchart[20];
16. 
    
17. int i,j,ctime,n,gi=0,wtime[20],ttime[20],quantum, cnt;
18. 
    
19. void getprocs();
20. void start();
21. void dispgchart();
22. void addgchart(int);
23. void disptimes();
24. int finished();
25. 
    
26. int main()
27. {
28. getprocs();
29. ctime=0;
30. start();
31. dispgchart();
32. disptimes();
33. }
34. 
    
35. void getprocs()
36. {
37. printf("\nHow many processes:");
38. scanf("%d",&n);
39. printf("\nPID\tATIME\tCPUB\n");
40. for(i=1; i<=n; i++)
41. {
42. scanf("%d%d%d",&proc[i].pid, &proc[i].atime, &proc[i].cpub);
43. }
44. printf("\nEnter Time Quantum\t");
45. scanf("%d",&quantum);
46. for(i=1; i<=n; i++)
47. {
48. printf("\n%d\t%d\t%d",proc[i].pid, proc[i].atime, proc[i].cpub);
49. }
50. }//getprocs
51. 
    
52. 
    
53. void start()
54. {
55. int pid;
56. while(!finished())
57. {
58. for(i=1; i<=n; i++)
59. {
60. cnt=0;
61. if(proc[i].atime <= ctime && proc[i].cpub!=0)
62. {
63. //wtime[i] = ctime-proc[i].atime;
64. wtime[i] = wtime[i]+(ctime-proc[i].atime);
65. addgchart(proc[i].pid);
66. while(cnt < quantum)
67. {
68. ctime++; 
69. proc[i].cpub--;
70. cnt++;
71. if(proc[i].cpub==0)//proc finished
72. {
73. printf("\nProc %d completed at time %d", proc[i].pid,ctime);
74. ttime[i] = ctime-proc[i].atime;
75. }//if
76. }//while
77. }//if
78. }//for
79. }//while
80. gchart[gi].etime = ctime;
81. }//start
82. 
    
83. int finished()
84. {
85. for(i=1; i<=n; i++)
86. {
87. if(proc[i].cpub != 0)
88. return 0;
89. }
90. return 1;
91. }
92. 
    
93. void addgchart(int pid)
94. {
95. gchart[++gi].pid = pid;
96. gchart[gi].stime = ctime;
97. gchart[gi-i].etime = gchart[gi].stime;
98. }
99. 
    
100. 
     
101. void dispgchart()
102. {
103. printf("\n");
104. for(i=1; i<=n; i++)
105. printf("|--");
106. printf("|\n");
108. for(i=1; i<=n; i++)
109. printf("| %d", gchart[i].pid);
110. printf("|\n");
111. 
     
112. for(i=1; i<=gi; i++)
113. printf("|--");
114. printf("|\n");
115. 
     
116. for(i=1; i<=gi; i++)
117. printf("%d  ",gchart[i].stime);
118. 
     
119. printf("%d\t",gchart[gi].etime);
120. }
121. 
     
122. void disptimes()
123. {
124. int sumwt=0, sumtt=0,pid;
125. printf("\n\n**Waiting Time**");
126. printf("\nPID\tWtimes");
127. for(i=1; i<=n; i++)
128. {
129. printf("\n%d\t%d",proc[i].pid, wtime[i]);
130. sumwt += wtime[i];
131. }
132. printf("\nAverage: %.2f", (float)sumwt/n);
133. printf("\n\n**Turnaround Time**");
134. printf("\nPID\tttime");
135. for(i=1; i<=n;i++)
136. {
137. printf("\n%d\t%d",i,ttime[i]);
138. sumtt+=ttime[i];
139. }
140. printf("\nAverage: %.2f", (float)sumtt/n);
141. printf("\n");
142. }