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Dario Alpern's site Home Page
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Java programs written by Dario Alpern

The programs in this site are:

  1. Generic Two integer variable equation solver: Diophantine equation ax2 + bxy + cy2 + dx + ey + f = 0 solver, where the unknowns x and y can be integer numbers only. Written in Java/JavaScript. Now it includes source code. Last updated on January 18th, 2001.

  2. Quadratic modular equation solver: Calculator that can solve equations of the form ax2 + bx + c = 0 (mod n).

  3. Ulam's Spiral: Java applet featuring a graphical view of prime numbers. Last updated on November 10th, 2000.

  4. Factorization using the Elliptic Curve Method: Applet capable of factoring numbers up to 100 digits long. Last updated on March 26th, 2001.

  5. Distance between cities: This is the first program that I have written in Java.

    It has a database of 105 cities, with their geographic locations. You can get the distance between any two cities of the database.

    The program contains two tests. In the first the user must input the distance between two random cities given by the computer (there are ten questions). In the second test there are a departure city, a destination city, and four more. The user should minimize the distance traveled by passing through the six cities.

    Press here to run the program

    Press here to obtain the source code