Python - Intersection of two String

String intersection finds the common characters between two strings. Python offers multiple approaches: iterating through characters or using set operations for efficient intersection.

Using Character Iteration

This method iterates through the first string and adds characters that exist in both strings while maintaining order ?

# initializing the string
string_1 = 'tutorialspoint'
string_2 = 'tut'

result = ''

# finding the common chars from both strings
for char in string_1:
    if char in string_2 and not char in result:
        result += char

# printing the result
print(result)

tu

Using Set Intersection

Converting strings to sets allows us to use the intersection method for finding common characters ?

# initializing the string
string_1 = 'tutorialspoint'
string_2 = 'tut'

# intersection
result = set(string_1).intersection(string_2)

# converting to string
result_str = ''.join(result)

# printing the result
print(result_str)

tu

Using Set Intersection with & Operator

The ampersand operator provides a more concise way to find set intersection ?

string_1 = 'tutorialspoint'
string_2 = 'tut'

# using & operator for intersection
result = set(string_1) & set(string_2)
result_str = ''.join(sorted(result))

print(result_str)

tu

Comparison

Conclusion

Use character iteration when order preservation is important. For better performance with large strings, use set intersection methods which offer O(n+m) time complexity.