Count of Subarrays not containing all elements of another Array

// C# program to implement above approach
using System;
using System.Collections.Generic;

class GFG
{
  public static int MOD = 1000000007;

  // Function to count subarrays that
  // do not contain target array
  public static int countSubarrays(List<int> nums, List<int> target)
  {
    // Size of nums
    int N = nums.Count;

    // The total number of subarrays in nums[]
    long ans = ((long)N * (long)(N + 1))/2;

    // Map to store frequency
    Dictionary<int, int> freq = new Dictionary<int, int>();
    HashSet<int> active = new HashSet<int>(target);

    // Left pointer as mentioned above
    int left = 0;

    // Right pointer loop until all elements
    // in target are present
    for (int right = 0; right < N; right++)
    {
      // Populating the frequency
      // of elements in freq map
      if (active.Contains(nums[right])){
        int val;
        if (freq.TryGetValue(nums[right], out val))
        {
          // yay, value exists!
          freq[nums[right]] = val + 1;
        }
        else
        {
          // darn, lets add the value
          freq.Add(nums[right], 1);
        }
      }

      // When there is the possibility
      // that it contains the subarray
      // target then only target and
      // freq size will be equal
      while (freq.Count == target.Count) {

        // Total subarray-count of
        // subarray which contains
        // target = Count of
        // subarray which does not
        // contain target which is
        // our required ans
        ans -= (N - right);

        if (active.Contains(nums[left])) {
          --freq[nums[left]];
          if (freq[nums[left]] == 0){
            // erasing element
            // frequency from left
            // pointer
            freq.Remove(nums[left]);
          }
        }

        // Advance the left pointer
        // until we no longer have
        // every number in target
        left++;
      }
    }

    // Returning ans mod 10^9+7
    return (int)(ans % MOD);
  }

  // Driver Code
  public static void Main(string[] args)
  {
    // Input Array
    List<int> nums = new List<int>{
      1, 2, 2
      };
    List<int> target = new List<int>{
      1, 2
      };

    // Function call and printing result.
    Console.Write(countSubarrays(nums, target));
  }
}

// This code is contributed by subhamgoyal2014.

using System;

public class CountSubarrays
{
    public static int Countsubarrays(int[] nums, int[] target)
    {
        int count = 0;
        int n = nums.Length;

        // Loop through all possible subarrays
        for (int i = 0; i < n; i++)
        {
            for (int j = i; j < n; j++)
            {
                // Check if the subarray contains all elements of the target array
                if (!ContainsAll(nums, i, j, target))
                {
                    count++;
                }
            }
        }

        return count;
    }

    public static bool ContainsAll(int[] nums, int start, int end, int[] target)
    {
        foreach (int x in target)
        {
            bool found = false;
            for (int i = start; i <= end; i++)
            {
                if (nums[i] == x)
                {
                    found = true;
                    break;
                }
            }
            if (!found)
            {
                return false;
            }
        }
        return true;
    }

    public static void Main(string[] args)
    {
        int[] nums1 = { 1, 2, 2 };
        int[] target1 = { 1, 2 };
        int[] nums2 = { 1, 2, 3 };
        int[] target2 = { 1 };

        Console.WriteLine(Countsubarrays(nums1, target1)); // Output: 4
        Console.WriteLine(Countsubarrays(nums2, target2)); // Output: 3
    }
}