Python – Replace to K at ith Index in String
Given a String, replace ith index by K value.
Input : test_str = ‘geeks5geeks’, K = ‘7’, i = 5
Output : ‘geeks7geeks’
Explanation : Element is 5, converted to 7 on ith index.Input : test_str = ‘geeks5geeks’, K = ‘7’, i = 6
Output : ‘geeks56eeks’
Explanation : Element is g, converted to 7 on ith index.
Method #1 : Using string slicing
In this, we perform the slicing of pre string, till i, and then add K, then add post values, using string slice method.
Python3
# Python3 code to demonstrate working of # Replace to K at ith Index in String # using string slicing # initializing strings test_str = 'geeks5geeks' # printing original string print ( "The original string is : " + str (test_str)) # initializing K K = '4' # initializing i i = 5 # the replaced result res = test_str[: i] + K + test_str[i + 1 :] # printing result print ( "The constructed string : " + str (res)) |
The original string is : geeks5geeks The constructed string : geeks4geeks
Method #2 : Using join() + generator expression
In this, we perform the task of checking for ith index and conditionally appending K, using generator expression and convert the result into string using join().
Python3
# Python3 code to demonstrate working of # Replace to K at ith Index in String # using join() + generator expression # initializing strings test_str = 'geeks5geeks' # printing original string print ( "The original string is : " + str (test_str)) # initializing K K = '4' # initializing i i = 5 # the replaced result res = ''.join(test_str[idx] if idx ! = i else K for idx in range ( len (test_str))) # printing result print ( "The constructed string : " + str (res)) |
The original string is : geeks5geeks The constructed string : geeks4geeks