Count Subsequences Problem Statement

Given an integer array ARR of size N, your task is to find the total number of subsequences in which all elements are equal.

Explanation:

A subsequence of an array is derived by removing some of the elements of the array without changing the order of the remaining elements.

Input:

The first line contains an integer 'T' denoting the number of test cases. Each test case is as follows: The first line contains an integer 'N' denoting the size of the array. The second line contains 'N' space-separated integers representing the elements of the array.

Output:

For each test case, output the total number of subsequences where all elements are the same. Each test case's result should be printed on a new line.

Example:

Input:
2
3
1 1 2
4
3 3 3 3
Output:
3
14

Constraints:

  • 1 ≤ T ≤ 100
  • 1 ≤ N ≤ 105
  • 0 ≤ ARR[i] ≤ 109
  • Time Limit: 1 second

Note:

The result must be calculated modulo 109 + 7. Implement the function; you don't need to print anything.
AnswerBot
4mo

Count the total number of subsequences in which all elements are equal in an integer array.

  • Iterate through the array and count the frequency of each element.

  • Calculate the total number of subsequences ...read more

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