Below is the attached code to calculate max sub sequence of length l which is entered by user.Algorithm calculate the max subsequence in O(n) time.The logic are as follows:- 1.)Take two variable sum and maxsum. 2.)Run the algorithm till (i+1)<=l and calculate the sum. 3.)After when i+1)>l ,then it follows the recursion like this. sum(n)=sum(n-1)+array[i]-array[i-l] ,it shows sum of next elements of length l is equal to sum of previous l elements + current element - (first element in sum of previous element) for an example:- 2 -1 -2 3 4 then it has following sum of length 3 1.) 2+(-1)+(-2) = -2 2.) (-1)+(-2)+3 = -1 3.) (-2)+3+4 = 5 max sub sequence is 5. Please find the below code ,you can try and run the below code on http://www.compileonline.com/compile_c_online.php Happy coding _________________________________________________________________________________ #include <stdio.h> #include ...