Balanced Partitioning

You are given an array of integers representing the weights of various items. Your task is to determine the minimum number of partitions such that the sum of weights in each partition is equal. You must create at least one partition, and each item's weight must belong to exactly one partition. If it is impossible to partition the array this way, return -1. Input format: - A single line containing N (1 ≤ N ≤ 100000), the number of elements in the array. - A second line containing N integers, each representing an element of the array. Output format: - A single integer indicating the minimum number of partitions possible, or -1 if impossible. Example: Input: 6 3 1 1 2 2 3 Output: 3