Use of Split them Test
The problem requires partitioning an array of N natural numbers into subarrays such that each element belongs to exactly one subarray, and no two subarrays contain the same natural number. The task is to find the total number of valid partitions in which the given array can be subdivided completely, and return it modulo 10^9+7.
This problem requires a good understanding of array partitioning and the use of modulo arithmetic. The solution involves iterating over the array and keeping track of the elements in each subarray, and checking that no element appears in more than one subarray. To count the number of valid partitions, we can use dynamic programming, keeping track of the number of valid partitions for each subarray size. Finally, we return the total number of valid partitions modulo 10^9+7.