Python – Capitalize repeated characters in a string
- Given an input string with lowercase letters, the task is to write a python program to identify the repeated characters in the string and capitalize them.
Examples:
Input: programming language
Output: pRoGRAMMiNG lANGuAGe
Explanation: r,m,n,a,g are repeated elements
Input: geeks for geeks
Output: GEEKS for GEEKS
Explanation: g,e,k,s are repeated elements
Approach 1:
- We have to keep the character of a string as a key and the frequency of each character of the string as a value in the dictionary.
- Traverse the string and check the frequency of each character using a dictionary if the frequency of the character is greater than one then change the character to the uppercase using the upper() function.
Implementation:
Python3
def RepeatedUpper(s):
dic = {}
for i in s:
if i in dic:
dic[i] = dic[i] + 1
else :
dic[i] = 1
ans = ''
for i in s:
if dic[i] > 1 :
i = i.upper()
ans = ans + i
return ans
s = 'geeks for geeks'
print (RepeatedUpper(s))
|
Time Complexity: O(n)
Auxiliary Space: O(n)
Approach 2:
Using count() function.If count is greater than 1 then the character is repeated.Later on used upper() to convert to uppercase
Python3
s = "programming language"
new_str = ""
for i in s:
if (i! = "" and s.count(i)> 1 ):
new_str + = i.upper()
else :
new_str + = i
print (new_str)
|
Output
pRoGRAMMiNG lANGuAGe
Time Complexity: O(n2) -> (count function + loop)
Auxiliary Space: O(n)
Approach 3: Using replace() and len() methods
Python3
s = "programming language"
length = len (s)
new_str = ""
for i in s:
x = s.replace(i,"")
if ( len (x)! = length - 1 ):
new_str + = i.upper()
else :
new_str + = i
print (new_str)
|
Output
pRoGRAMMiNG lANGuAGe
Time Complexity: O(n2) -> (replace function + loop)
Auxiliary Space: O(n)
Approach #4 : Using Counter() function
Python3
from collections import Counter
s = "programming language"
new_str = ""
freq = Counter(s)
for i in s:
if (i ! = "" and freq[i] > 1 ):
new_str + = i.upper()
else :
new_str + = i
print (new_str)
|
Output
pRoGRAMMiNG lANGuAGe
Time Complexity: O(n)
Auxiliary Space: O(n)
Approach #5 : Using List Comprehension
In this approach, we first create a Counter object to store the frequency of each character in the string. Then, we use a list comprehension to iterate over the characters in the string, and for each character, we check if its frequency is greater than 1. If it is, we convert it to uppercase using upper(). Finally, we use join() to concatenate the characters and return the result as a single string.
Python3
from collections import Counter
def capitalize_repeated_chars(s):
freq = Counter(s)
return "".join([char.upper() if freq[char] > 1 else char for char in s])
s = "programming language"
print (capitalize_repeated_chars(s))
|
Output
pRoGRAMMiNG lANGuAGe
Time complexity: O(n), where n is the length of the input string.
Auxiliary space: O(n), for storing the frequency of each character in the Counter object.
Approach #6 : Using operator.countOf() method
- In this approach we iterate over the characters in the string.
- For each character, we check if its frequency(operator.countOf()) is greater than 1.
- Initialize a new_str with empty string.
- If it is, we convert it to uppercase using upper() and concatenate to new_str.
- If not concatenate the character as it is to new_str.
- Finally print the new_str.
Python3
s = "programming language"
new_str = ""
import operator
for i in s:
if (i! = "" and operator.countOf(s,i)> 1 ):
new_str + = i.upper()
else :
new_str + = i
print (new_str)
|
Output
pRoGRAMMiNG lANGuAGe
Time complexity: O(n), where n is the length of the input string.
Auxiliary space: O(n), for storing the frequency of each character.
Last Updated :
20 Feb, 2023
Like Article
Save Article
Share your thoughts in the comments
Please Login to comment...