Python: Find the first two elements of a given list whose sum is equal to a given value

Last update on December 21 2024 07:30:56 (UTC/GMT +8 hours)

Write a Python program to find the first two elements of a given list whose sum is equal to a given value. Use the itertools module to solve the problem.

Sample Solution:

Python Code:

import itertools as it
def sum_pairs_list(nums, n):
    for num2, num1 in list(it.combinations(nums[::-1], 2))[::-1]:
        if num2 + num1 == n:
            return [num1, num2]

nums = [1,2,3,4,5,6,7]     
n = 10
print("Original list:",nums,": Given value:",n)   
print("Sum of pair equal to ",n,"=",sum_pairs_list(nums,n))

nums = [1,2,-3,-4,-5,6,-7]     
n = -6
print("Original list:",nums,": Given value:",n)   
print("Sum of pair equal to ",n,"=",sum_pairs_list(nums,n))

Sample Output:

Original list: [1, 2, 3, 4, 5, 6, 7] : Given value: 10
Sum of pair equal to  10 = [4, 6]
Original list: [1, 2, -3, -4, -5, 6, -7] : Given value: -6
Sum of pair equal to  -6 = [1, -7]

Python Code Editor:

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