Problem
Design a program that will plot a given set of points on a graph. The input to the program will be a text file, each line of which contains two numbers that are the x and y coordinates of a point to be plotted. The program will use a function to plot one such pair of coordinates. The details of the function plotting involve the specific method of plotting and cannot be written since they depend on the requirements of the plotting equipment, which we do not know. Before plotting the points the program needs to know the maximum and minimum values of x and y that appear in its input file. The program should therefore use another function bounds that will read the whole file and determine these four maxima and minima. Afterward, another function is used to draw and label the axes; then the file can be reset and the individual points plotted.
(a) Write the main program, not including the functions.
(b) Write the function bounds.
(c) Write the preconditions and postconditions for the remaining functions together with appropriate documentation showing their purposes and their requirements.