Given a string that contains both upper and lower case characters in it. The task is to count number of upper and lower case characters in it without using in-built functions.

Counting the upper and lower case characters of a string can be easily done using isupper() and islower() functions, refer this. But doing the same without help of any inbuilt function is quite exciting. Let’s see how this can be done :

Examples :

Input : Introduction to Python
Output : Lower Case characters : 18 Upper case characters : 2

Input :  Welcome to GeeksforGeeks
Output : Lower Case characters : 19  Upper case characters: 3

Below is the implementation of above idea :

# Python3 program to count upper and
# lower case characters without using
# inbuilt functions
def upperlower(string):

	upper = 0
	lower = 0

	for i in range(len(string)):
		
		# For lower letters
		if (ord(string[i]) >= 97 and
			ord(string[i]) <= 122):
			lower += 1

		# For upper letters
		elif (ord(string[i]) >= 65 and
			ord(string[i]) <= 90):
			upper += 1

	print('Lower case characters = %s' %lower,
		'Upper case characters = %s' %upper)

# Driver Code
string = 'GeeksforGeeks is a portal for Geeks'
upperlower(string)

Output:

Lower case characters = 27 Upper case characters = 3

Alternative Method:-

s = "The Geek King"
l,u = 0,0
for i in s:
	if (i>='a'and i<='z'):
		
		# counting lower case
		l=l+1				
	if (i>='A'and i<='Z'):
		
		#counting upper case
		u=u+1
		
print('Lower case characters: ',l)
print('Upper case characters: ',u)

Output:

Lower case characters:  8
Upper case characters:  3