Question

Write a program that allows the user to navigate the lines of text in a file.

The program should prompt the user for a filename and input the lines of text into a list.

The program then enters a loop in which it prints the number of lines in the file and prompts the user for a line number.

Actual line numbers range from 1 to the number of lines in the file. If the input is 0, the program quits. Otherwise, the program prints the line associated with that number. An example file and the program input and output is shown below: example.txt Line 1. Line 2. Line 3. Enter the input file name: example.txt The file has 3 lines. Enter a line number [0 to quit]: 2 2 : Line 2. The file has 3 lines. Enter a line number [0 to quit]: 0

There is an example.txt file and a navigate.py file so I need to know what to put in each.

Answer 1

file=input('Enter the input file name: ')
lines=[]
with open(file,'r') as f:
    for line in f:
        lines.append(line.strip())

print('\nThe file has',len(lines),'lines')
lineNum=int(input('Enter a line number [0 to quit]: '))
while lineNum!=0:
    if lineNum<=len(lines):
        print(lineNum,':',lines[lineNum-1])
    else:
        print('There are not enough lines in the file')
    print('\nThe file has', len(lines), 'lines')
    lineNum = int(input('Enter a line number [0 to quit]: '))