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Coding Challenge 1: Array Manipulation
Problem Statement:
Given an array of integers and a target sum, determine if there exists a contiguous
subarray within the array that sums up to the target. Return true if such a subarray exists,
otherwise return false.
Example:
Input: arr = [4, 2, 7, 1, 9, 5], target = 14
Output: true
Explanation: The subarray [7, 1, 9] sums up to 14, which is equal to the target.
Constraints:
- The array will contain between 1 and 100,000 elements.
- The elements in the array and the target sum will be between -1,000,000,000 and
1,000,000,000.
Expected Time Complexity: O(n), where n is the length of the array.
Expected Space Complexity: O(1)
