Determining if a pair of integers in a list sums to a target value

Problem

Given a list of integers and a target value, determine if there is a pair of integers in the list that sum to the target value.
Example input: [1, 2, 3, 4, 5], target=6
Example output: True (1 + 5 = 6)

Solution

This solution is in Python. Our A.I. can create solutions in multiple languages.

kayakane

def sum_to_target(lst, target):
    
    This function takes a list of integers and a target value and returns True if there is a pair of integers in the list that sum to the target value.
    
    # Create a set of the list
    s = set(lst)
    # Iterate through the list
    for i in lst:
        # If the target minus the current value is in the set, return True
        if target - i in s:
            return True
    # If the target minus the current value is not in the set, return False
    return False

# Test cases
print(sum_to_target([1, 2, 3, 4, 5], 6))
print(sum_to_target([1, 2, 3, 4, 5], 7))
print(sum_to_target([1, 2, 3, 4, 5], 8))
print(sum_to_target([1, 2, 3, 4, 5], 9))
print(sum_to_target([1, 2, 3, 4, 5], 10))
print( sum_to_target([1, 2, 3, 4, 5], 11))
print(sum_to_target([1, 2, 3, 4, 5], 12))
print(sum_to_target([1, 2, 3, 4, 5], 13))
print(sum_to_target([1, 2, 3, 4, 5], 14))
print(sum_to_target([1, 2, 3, 4, 5], 15))


This solution is optimal because it only iterates through the list once and uses a set to check if the target minus the current value is in the set.