Python 1

Problems

1. Write a program which will open a text file and print the last 5 lines

2. Write a program which will print the length of the longest line in a text file

3. Suppose you have a text file each line of which is a single word; for example:

      hello
      ant
      cat
      elephant
   

Write a Python program which will display the lines in sorted order. The output in the above case should be:

     ant
     cat
     elephant
     hello

4. Write a Python program which will print all lines of a text file which contains the following pattern:

    An upper case A followed by any number of digits ending with an upper case B
   

For example, if the file contains lines like these:

    helloA01123Bpqr
    A9812BCqtmn

those lines should be printed on to the screen. Use regular expressions for solving this.

5. Write a Python program which will find out the largest file in the current directory. (hint: use "listdir" function from "os" module to find out names of all files; use the "stat" function from "os" module to get size of each file)

6. Read about the "binary search" algorithm on the net. Write a Python function to implement the binary search algorithm. The function should look like this:

         def binsearch(a, n):
              # Check whether number "n" is present in a sorted list "a"
              # If present, return index of the location where the number is present
              # Otherwise, return -1