Python: Find the first non-repeating character in given string
Python String: Exercise-51 with Solution
Write a Python program to find the first non-repeating character in given string.
Sample Solution:-
Python Code:
def first_non_repeating_character(str1):
char_order = []
ctr = {}
for c in str1:
if c in ctr:
ctr[c] += 1
else:
ctr[c] = 1
char_order.append(c)
for c in char_order:
if ctr[c] == 1:
return c
return None
print(first_non_repeating_character('abcdef'))
print(first_non_repeating_character('abcabcdef'))
print(first_non_repeating_character('aabbcc'))
Sample Output:
a d None
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Previous: Write a Python program to split a string on the last occurrence of the delimiter.
Next:Write a Python program to print all permutations with given repetition number of characters of a given string
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Python: Tips of the Day
What is the difference between Python's list methods append and extend?
append: Appends object at the end.
x = [1, 2, 3] x.append([4, 5]) print (x)
Output:
[1, 2, 3, [4, 5]]
extend: Extends list by appending elements from the iterable.
x = [1, 2, 3] x.extend([4, 5]) print (x)
Output:
[1, 2, 3, 4, 5]
Ref: https://bit.ly/2AZ6ZFq
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