There is a matrix consisting of positive integers, negative integers, and zeroes. A robot travels from top left element to the bottom right element. It can only  moves right or moves down in each step. And it cannot pass elements with negative  integers. At each element along the path, for each (above, below, left, right)  adjacent off-path element with negative integers, its negative value will be  added to the sum of the path, i.e., it reduces the value of the path. This program program reads a matrix data file (one row per  line with TAB character as the delimiter), and print out the paths.