Python Bisect: Find the first occurrence of a given number in a sorted list using Binary Search
Python Bisect: Exercise-4 with Solution
Write a Python program to find the first occurrence of a given number in a sorted list using Binary Search (bisect).
Sample Solution:
Python Code:
from bisect import bisect_left
def Binary_Search(a, x):
i = bisect_left(a, x)
if i != len(a) and a[i] == x:
return i
else:
return -1
nums = [1, 2, 3, 4, 8, 8, 10, 12]
x = 8
num_position = Binary_Search(nums, x)
if num_position == -1:
print(x, "is not present.")
else:
print("First occurrence of", x, "is present at index", num_position)
Sample Output:
First occurrence of 8 is present at index 4
Flowchart:
Visualize Python code execution:
The following tool visualize what the computer is doing step-by-step as it executes the said program:
Python Code Editor:
Contribute your code and comments through Disqus.
Previous: Write a Python program to insert items into a list in sorted order.
Next: Write a Python program to find the index position of the largest value smaller than a given number in a sorted list using Binary Search (bisect).What is the difficulty level of this exercise?
Test your Programming skills with w3resource's quiz.
Python: Tips of the Day
Find current directory and file's directory:
To get the full path to the directory a Python file is contained in, write this in that file:
import os dir_path = os.path.dirname(os.path.realpath(__file__))
(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)
To get the current working directory use
import os cwd = os.getcwd()
Documentation references for the modules, constants and functions used above:
- The os and os.path modules.
- The __file__ constant
- os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
- os.path.dirname(path) (returns "the directory name of pathname path")
- os.getcwd() (returns "a string representing the current working directory")
- os.chdir(path) ("change the current working directory to path")
Ref: https://bit.ly/3fy0R6m
- New Content published on w3resource:
- HTML-CSS Practical: Exercises, Practice, Solution
- Java Regular Expression: Exercises, Practice, Solution
- Scala Programming Exercises, Practice, Solution
- Python Itertools exercises
- Python Numpy exercises
- Python GeoPy Package exercises
- Python Pandas exercises
- Python nltk exercises
- Python BeautifulSoup exercises
- Form Template
- Composer - PHP Package Manager
- PHPUnit - PHP Testing
- Laravel - PHP Framework
- Angular - JavaScript Framework
- Vue - JavaScript Framework
- Jest - JavaScript Testing Framework