Need help creating a program please

A main function is required which accepts a single 1xn cell array of decimal numbers as characters and must perform long addition on these n whole numbers to return the sum as a character array. This function must be named AccuSumNet and it must use no other inputs and produce no other outputs apart from those described in this brief. You may make use of a single subroutine in AccuSumNet. The program must be entirely silent i.e. it may not employ any GUI or display to the console.

[James Tursa]

What have you done so far? What specific problems are you having with your code? As I read the problem, an example of an input and output would be

Input: {'83','42'}

Output: '125'

That is, the input is a cell array, and each cell contains a whole number as a character string. You need to add them up as if they were decimal numbers and produce the single character string output containing the sum.