How will the code do that? What is the logic?

What does the code need to remember to be able to restart the summing for the next numbers in the row?

What should it do when some where in the search through the values in a row it finds a series of numbers with the right sum?

You should take a piece of paper and a pencil, write a series of numbers in a row and then work out the logic. Draw pointers under the numbers to represent the indexes into the array. Label them and see how the indexes need to be moved and used to solve the problem.