Answer to Question #128387 in C# for MD RASEL BHUYAN

Question

Write a function that will merge the contents of two sorted (ascending order)
arrays of type double values, storing the result in an array output parameter
(still in ascending order). The function should not assume that both its input
parameter arrays are the same length but can assume that one array does not
contain two copies of the same value. The result array should also contain no
duplicate values.
Hint: When one of the input arrays has been exhausted, do not forget to copy
the remaining data in the other array into the result array.
Test your function with cases in which (1) the first array is exhausted first, (2) the second array is exhausted first, and (3) the two arrays are exhausted at the same time (i.e., they end with the same value). Remember that the arrays input to this function
must already be sorted .

Answer 1

    double[] merge(double[] firstArr, double[] secondArr)
    {
      double[] resArr = new double[firstArr.Length + secondArr.Length];

      int firstPos = 0, secondPos = 0, resPos = 0;
      double a, b;

      while (firstPos < firstArr.Length && secondPos < secondArr.Length)
      {
        a = firstArr[firstPos];
        b = secondArr[secondPos];

        if (a < b)
        {
          resArr[resPos++] = a;
          firstPos++;
        }
        else if (a > b)
        {
          resArr[resPos++] = b;
          secondPos++;
        }
        else
        {
          resArr[resPos++] = a;  // or b
          firstPos++;
          secondPos++;
        }
      }

      if (firstPos >= firstArr.Length)
      {
        for (int i = secondPos; i < secondArr.Length; i++)
          resArr[resPos++] = secondArr[i];
      }
      else  // secondPos >= secondArr.Length
      {
        for (int i = firstPos; i < firstArr.Length; i++)
          resArr[resPos++] = firstArr[i];
      }

      Array.Resize(ref resArr, resPos);       

      return resArr;
    }