Mars Pathfinder 1.0 is a one-screen DOS app. The 2.0 version is a full-blown Windows app with inputs, help screens, and full-color printouts of the solution trajectory. Visit the 2002 HTML code website (best viewed on a desktop PC).
Once you download it, it self-extracts, and sets up the install routine. It installs in a separate directory and even adds an icon on your program menu.
There are many help screens that explain how the program works and how to interpret the results.
You can run several cases, then add gravity-assist options that lower the fuel consumption at both ends of the trajectory.
Once you make your selections and hit “Calculate” it takes about 30 seconds on a 486 PC (this was circa 2000). Then it plots out the results in color, showing the path followed by Earth, Mars, and the spacecraft.
It then shows you how the program adjusted your inputs to reach Mars.
You can also get a full printout of the trajectory in 3D (x-, y-, and z-dimensions) accurate to 16 significant digits, less than a centimeter from start to finish.