20. Write A Python Program To Count The Number Of Lines In A Text File. Code Example


Example 1: Write a Python program to count the number of lines in a text file.

def countlines(fname,mode='r+'): 	count=0 	with open(fname) as f: 		for _ in f: 			count += 1 	print('total number of lines in file : ',count)  countlines('file1.txt')  ##########################  with open('file1.txt') as f: 	print(sum(1 for _ in f)) ########################## with open('file1.txt') as f: 	for lno , line in enumerate(f,1): 		pass 	print('total lines:',lno)  ########################### '''You can use len(f.readlines()),  but this will create an additional list in memory,   which won't even work on huge files that don't fit in memory.  '''

Example 2: Write a Python program to count the number of lines in a text file.

def countlines(fname,mode='r+'): 	count=0 	with open(fname) as f: 		for _ in f: 			count += 1 	print('total number of lines in file : ',count)  countlines('file1.txt')  ##########################  with open('file1.txt') as f: 	print(sum(1 for _ in f))  ########################### '''You can use len(f.readlines()),  but this will create an additional list in memory,   which won't even work on huge files that don't fit in memory.  '''

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