Find the first non repeating character in a string

Veröffentlicht am: 22 Juli 2024
auf dem Kanal: pythonbuzz

243

#coding #phython #learnpython #learn #programming #pythonlearning #top #python #python3 #pythonforbeginners #pythonstatus #pythonprogramming #pythonlearning #phython #pythonprogramming #python#python interview questions#python interview questions and answers#python interview questions for freshers#python interview#python developer interview questions#python coding interview questions#top python interview questions#python interview preparation#python interview questions and answers for freshers#python interview questions and answers for experienced#python programming interview questions#python job interview#python interview coding questions

=====================================================

from collections import Counter

s = "swiss"
char_count = Counter(s)

for char in s:
if char_count[char] == 1:
print("First non-repeating character:", char)
break

let's break down the code step-by-step:

1. **Import the Counter class from the collections module**:
```python
from collections import Counter
```
The `Counter` class is part of the `collections` module and is used to count the occurrences of elements in an iterable (like a string, list, etc.).

2. **Define the string `s`**:
```python
s = "swiss"
```
Here, we have a string `s` with the value `"swiss"`.

3. **Create a Counter object to count character occurrences**:
```python
char_count = Counter(s)
```
`Counter(s)` creates a dictionary-like object where keys are characters from the string `s` and values are their counts. For the string `"swiss"`, `char_count` will be `Counter({'s': 3, 'w': 1, 'i': 1})`.

4. **Iterate over each character in the string `s`**:
```python
for char in s:
```
This loop goes through each character in the string `s`.

5. **Check if the character occurs only once**:
```python
if char_count[char] == 1:
```
Inside the loop, this condition checks if the current character `char` appears only once in the string `s` by looking it up in the `char_count` dictionary.

6. **Print the first non-repeating character and break the loop**:
```python
print("First non-repeating character:", char)
break
```
If the condition is true (i.e., the character count is 1), it prints the character and immediately exits the loop with the `break` statement. This ensures that only the first non-repeating character is printed.

Putting it all together, the code counts the occurrences of each character in the string `s`, then iterates through the string to find and print the first character that occurs only once. For the string `"swiss"`, the first non-repeating character is `"w"`, so the output will be:

```
First non-repeating character: w
```

Auf dieser Seite können Sie das Online-Video Find the first non repeating character in a string mit der Dauer stunde minuten sekunde in guter Qualität ansehen, das der Benutzer pythonbuzz 22 Juli 2024 hochgeladen hat, den Link mit Freunden und Bekannten teilen, dieses Video wurde auf Youtube bereits 243 Mal angesehen und es wurde von like den Zuschauern gefallen. Viel Spaß beim Betrachtenden Zuschauern gefallen!