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Python: Generate the combinations of n distinct objects taken from a list

Python List: Exercise - 82 with Solution

Write a Python program to generate the combinations of n distinct objects taken from the elements of a given list.

Sample Solution:

Python Code:

def combination(n, n_list):
    if n<=0:
        yield []
        return
    for i in range(len(n_list)):
        c_num = n_list[i:i+1]
        for a_num in combination(n-1, n_list[i+1:]):
            yield c_num + a_num
n_list = [1,2,3,4,5,6,7,8,9]
print("Original list:") 
print(n_list)
n = 2
result = combination(n, n_list)
print("\nCombinations of",n,"distinct objects:")
for e in result:
     print(e)


Sample Output:

Original list:
[1, 2, 3, 4, 5, 6, 7, 8, 9]

Combinations of 2 distinct objects:
[1, 2]
[1, 3]
[1, 4]
[1, 5]
[1, 6]
[1, 7]
[1, 8]
[1, 9]
[2, 3]
[2, 4]
[2, 5]
[2, 6]
[2, 7]
[2, 8]
[2, 9]
[3, 4]
[3, 5]
[3, 6]
[3, 7]
[3, 8]
[3, 9]
[4, 5]
[4, 6]
[4, 7]
[4, 8]
[4, 9]
[5, 6]
[5, 7]
[5, 8]
[5, 9]
[6, 7]
[6, 8]
[6, 9]
[7, 8]
[7, 9]
[8, 9]

Pictorial Presentation:

Python List: Generate the combinations of n distinct objects taken from a list.

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Flowchart: Generate the combinations of n distinct objects taken from a list.

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Previous: Write a Python program to extract a given number of randomly selected elements from a given list.
Next: Write a Python program to round every number of a given list of numbers and print the total sum multiplied by the length of the list.

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Python: Tips of the Day

Big Number Readability:

you can separate zeros with underscore (_)

print(2_000_000)
print(2_000_000 +1)

Output:

2000000
2000001