Advance Operating System Problems

Problem1 : Write a script in shell or in python , which is able to store 50 commands which you have  previous entered through terminal  and execute each command .

Problem 2: Execute the program that will read the file content and print those content adding with line number and arranged in the alphabetical order

Problem 3: Read a file of 20 lines , information then print with line number and another file print only word list with their frequency of occurance and character counts in each word as another description of the word into the third file . 


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Solutions

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Solution 1: Shell script
          
Step 1:Open terminal type Step 2 Code .
Step 2: ( We assume you have typed 50 commands through terminal )

           fc -ln -50 > abc.sh
Description :  The fc command is a command line utility for listing, editing and re-executing commands previously entered into an interactive shell.
Above command will save 50 previous commands into abc.sh 

Step 3: chmod +x abc.sh
//give execute permission  

Step 4: ./abc.sh  
 //execute command


Solution 2 :  Please visit below url for file operation in Python

 https://www.digitalocean.com/community/tutorials/how-to-handle-plain-text-files-in-python-3#step-1-%E2%80%94-creating-a-text-file

https://stackoverflow.com/questions/19001402/how-to-count-the-total-number-of-lines-in-a-text-file-using-python

https://www.programiz.com/python-programming/examples/alphabetical-order
           
#open file
days_file = open("hem.txt",'r')

num_lines = sum(1 for line in open('hem.txt'))
#print(num_lines)

count=1

#make a list of item
lines=list(days_file)

for lin in lines:
    String=sorted(lin.split(), key=str.lower)
    str1 = ' '.join(String)
    print(count,str1)
    count=count+1

days_file.close();

Solution 3:

Please go below link for more

https://www.pitt.edu/~naraehan/python2/split_join.html
 https://developers.google.com/edu/python/strings

from collections import Counter
#open the file
filepath =open('xyz.txt') 

#code 1
#store all file in lines
lines=filepath.readlines()
list=[]
#call till 20 values
for i in range(20):
    #retrieve each line
    String=lines[i]
    print(i+1,":",String)
    #split each word
    words = String.split()
    list.extend(words)
    #print(words)
#print(list)

c=Counter(list)
c.values()

print("Word  Frequency Count")
for key,value in c.items():
    string=key
    print(key,value,len(string)-string.count(' '))






3 Files in a zip . 
I have used python 2.7+ .

https://drive.google.com/file/d/1Nn_K7hzge5nIhWX32xNeDNklo53CVsln/view?usp=sharing